Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/C4CY00660G

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s10562-014-1316-3

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.colsurfa.2014.04.056

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.jcat.2013.05.016

Language：English  

DOI： 10.1016/j.apcatb.2013.05.041

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.3390/catal3010219

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.cattod.2014.05.018

Publisher：Catalysis Today  

Manganese oxide catalysts with different structures and loading levels were supported on zeolite Y catalysts using a dry impregnation method for the oxidation of low concentrations of benzene with ozone. X-ray diffraction (XRD) and X-ray absorption fine structure (XAFS) studies revealed that manganese oxide was highly dispersed on the zeolite in a low oxidation state for those prepared with the acetate precursor, and highly oxidized and aggregated manganese oxide for those prepared with the nitrate precursor. In the reaction at 70 ℃, the benzene oxidation rate, CO2 selectivity, and ozone/benzene decomposition ratio were independent of the manganese loading, manganese precursor, and zeolite Y porosity. These catalytic properties were found to be less dependent on the manganese oxide structure. A slight increase in the reaction temperature enhanced both the catalytic activity and the catalyst performance, while the presence of water vapor had no significant impact. The XAFS analysis of the spent catalysts indicated that during the benzene decomposition reaction, the structure of the manganese oxide loaded on the catalyst was altered, and its oxidation state was uniformly reduced.

DOI： 10.1016/j.cattod.2024.115104

Web of Science

Scopus

Publisher：Catalysis Letters  

MnOX supported on a zeolite Y catalyst (MnOX/Y) is widely utilized for the removal of volatile organic compounds (VOCs), providing an understanding of catalyst structural changes and the factors influencing these changes. This study introduces a heat treatment method to recover the catalyst. The efficacy of the treated catalysts in enhancing the oxidation of benzene by ozone was improved. Investigation of the behavior of catalysts prepared from acetate and nitrate precursors revealed a common trend: MnOX in the catalysts was readily reduced to MnO by intermediate products, acids, aldehydes, and phenols formed during the benzene ozonation process, as evidenced by X-ray absorption fine structure temperature-programmed reduction and in situ Fourier-transform infrared spectroscopy analyses. Heat treatment at 200 °C was found to be insufficient for the restoration of the MnOX structure, which was attributed to the persistence of acids and hydrocarbons within the catalyst. 500 °C was determined to be more appropriate for the regeneration of the used catalysts, indicating the critical role of the heat treatment conditions in maintaining the effectiveness of the MnOX/Y catalysts in VOC removal applications. Graphical Abstract: (Figure presented.)

DOI： 10.1007/s10562-024-04836-2

Web of Science

Scopus

Publisher：Chemical Engineering Journal  

The bio-based production of essential chemicals is important for the sustainability of the chemical industry. Here, we demonstrate efficient olefin production from methyl oleate using Na substituted ZSM-5 (Na-ZSM-5) and microwave irradiation. Na-ZSM-5 exhibits superior microwave heating properties compared to H-ZSM-5 and other zeolites. It was more effective in converting methyl oleate to olefins such as ethylene and propylene than H-ZSM-5 or Y zeolites. Microwave irradiation promoted the conversion efficiency of methyl oleate by Na-ZSM-5, achieving an olefin yield over four times higher than that obtained with conventional heating (CH) using an electric furnace. Meanwhile, the aromatization to benzene, toluene and xylene (BTX) was suppressed using Na-ZSM-5, which was attributed to the removal of strong acid sites. In addition, in situ microwave XRD revealed that microwaves promoted temperature-dependent structural changes in Na-ZSM-5 at lower temperatures than CH, suggesting that microwaves form localized high temperatures in the zeolite. These localized high temperatures effectively enhance olefin production via microwave irradiation.

DOI： 10.1016/j.cej.2024.154737

Web of Science

Scopus

Publisher：Catalysts  

Transition metal oxides show high activity while still facing the challenges of low mineralization and poor durability in the ozone catalytic oxidation (OCO) of volatile organic compounds (VOCs). Improving the oxygen mobility and low-temperature reducibility of transition metal oxides was found to be an effective way to address the above challenges. Here, highly dispersed Ag was added to Mn3O4 via the co-precipitation oxalate route, and the obtained Ag/Mn3O4 exhibited higher mineralization and stability in benzene catalytic ozonation at room temperature. Compared to Mn3O4, the concentration of CO2 formed from benzene oxidation over Ag/Mn3O4 was significantly increased, from 585.4 ppm to 810.9 ppm, while CO generation was greatly suppressed to only one tenth of its original value (194 ppm vs. 19 ppm). In addition, Ag/Mn3O4 exhibited higher catalytic stability than Mn3O4. The introduction of Ag obviously improved the oxygen mobility and low-temperature reducibility of Mn3O4. Moreover, the highly dispersed Ag also promoted the activity of surface oxygen species and the chemisorption of benzene on Mn3O4. The above physicochemical properties contributed to the excellent catalytic performance and durability of Ag/Mn3O4. This research could shed light on the improvement in VOC mineralization via ozone catalytic oxidation.

DOI： 10.3390/catal14090554

Web of Science

Scopus

Publisher：Journal of Physical Chemistry C  

Microwave heating is an effective method for efficiently heating a target material, allowing the chemical reaction processes to proceed quickly. In catalytic reactions under microwave irradiation, it is essential to understand the relationship between the structure and physical properties of the material to be used as a catalyst and microwave heating. In this study, we focused on tungsten oxides, which absorb microwaves and convert them into heat, and we compared the microwave heating properties of tungsten oxides with different structures. The heating properties of tungsten oxides under microwave irradiation are highly dependent on their morphologies. WO3 nanoflakes with a monoclinic phase structure have a more rapidly heated surface than tungsten oxides with other morphologies. The heating characteristics of each tungsten oxide were consistent with the dielectric loss factor obtained by the perturbation method. Finite element analysis was used to gain a better understanding of the thermal distribution of materials during microwave irradiation.

DOI： 10.1021/acs.jpcc.4c02936

Web of Science

Scopus

Language：English   Publisher：Environmental Science and Pollution Research  

The development of technologies for highly efficient treatment of emissions containing low concentrations of volatile organic compounds (VOCs) remains an important challenge. Catalytic oxidation with ozone (catalytic ozonation) is useful for the oxidative decomposition of VOCs, particularly aromatic compounds, under ambient temperature conditions. Only inexpensive transition metal oxides are required as catalysts, and Mn-based catalysts are widely used for catalytic ozonation. This review describes the oxidation reaction mechanisms, reaction pathways of aromatic hydrocarbons, and dependence of the catalytic ozonation activity on the reaction conditions. The reasons why Mn oxides are effective in catalytic ozonation are also explained. The structure of the catalytic active sites and the types of supporting materials contributing to the reaction are also discussed in detail, with the aim of establishing a VOC control technology. In addition, recent progress in catalytic oxidation processes using ozone as an oxidant has been outlined, focusing on catalyst materials and reaction conditions.

DOI： 10.1007/s11356-024-34004-3

Scopus

PubMed

Publisher：Journal of the Taiwan Institute of Chemical Engineers  

Microwave-assisted catalytic reactions have been investigated for energy-efficient chemical processes. However, catalysts with comparatively high heating properties, activities, and economics have been developed with limited success. In this study, we investigated the catalytic properties of Ce addition to LaNiO3 catalyst, which has high CO oxidation activity and high microwave heating properties. Ce-added catalysts exhibited high heating properties under microwave heating. Increasing the Ce content in the catalyst enhanced the dielectric loss factor, the ability to absorb microwaves and convert them to heat, and improved the microwave heating properties of the catalyst. The catalytic activity toward CO oxidation over Ce-added catalysts decreased in the order of La0.8Ce0.2NiO3 > La0.9Ce0.1NiO3 > LaNiO3 at all oxygen partial pressures when compared to the same microwave power. To clarify the role of Ce addition, temperature programmed reduction (TPR) by H2, CO, and XAFS measurements were performed. TPR results suggested that Ce promotes oxygen mobility and then affects both CO oxidation and microwave heating properties.

DOI： 10.1016/j.jtice.2023.105041

Web of Science

Scopus

Publisher：Applied Catalysis A: General  

In this work, Mn-Ni solid solutions were obtained by doping Ni into MnOx via solution combustion synthesis and the resulting catalysts were then applied to benzene oxidation. Various characterizations revealed that Ni doping changed the metal oxygen bond parameters, such as coordination numbers (CNs) and bond length. Both Mn-O and Ni-O bonds in Mn-Ni solid solutions exerted reduced CNs, while the bond length of Mn-O bonds was extended, making the oxygen species more chemically reactive., which further improved physicochemical properties (such as reducibility, oxygen mobility, surface active oxygen species etc.) and catalytic performance. Remarkably, the solid solutions with a Mn/Ni molar ratio of 4:1 (named Mn4Ni1) showed Mn-O and Ni-O bonds with lower CNs and longer bond lengths, which enhanced the activity and mobility of oxygen species, reducibility and chemisorption capacity of benzene. Therefore, Mn4Ni1 demonstrated optimal benzene oxidation activity and showed the lowest T90 (192 °C). The potential reaction mechanism was proposed according to the analysis results of C6H6-TPSR and in-situ FTIR. Furthermore, promoted oxidation of benzene and phenolate species on Mn4Ni1 could inhibit accumulation of intermediates and avoid catalyst poisoning and deactivation. This strategy shed light to the design of catalysts in environmental catalysis and thermal catalysis.

DOI： 10.1016/j.apcata.2024.119575

Web of Science

Scopus

Language：English   Publisher：ACS Nano  

The interaction between a metal and a support, which is known as the metal-support interaction, often plays a determining role in the catalytic properties of supported metal catalysts. Herein, we have developed model Pt/CeO2 catalysts, which enabled us to investigate the interface atomic and electronic structures between Pt and the {001}, {011}, and {111} planes of CeO2 using scanning transmission electron microscopy and electron energy-loss spectroscopy. We found that the number of Ce3+ ions around the Pt nanoparticles followed the order {001} > {011} > {111}, which was the opposite order of the generally accepted stability of low index surfaces of CeO2. Systematic first-principles calculations revealed that the presence of Pt nanoparticles facilitated the formation of oxygen vacancies and that the appearance of the Ptδ+ state was preferred when Pt nanoparticles were in contact with CeO2 {001} planes due to direct charge transfer from Pt to CeO2. These results provide important insights into the nature of the metal-support interaction for a comprehensive understanding of the properties of supported metal catalysts.

DOI： 10.1021/acsnano.3c09092

Web of Science

Scopus

PubMed

Publisher：ChemCatChem  

Selective oxidation reactions are crucial in producing various chemicals in the industry. However, most catalytic processes for these reactions use harsh reaction conditions. Recently, heterogeneous photo(electro)catalysis has been considered promising for selective oxidation reactions under mild conditions. Semiconductor materials are frequently used as heterogeneous photocatalysts because they can produce active species that contribute to the oxidation of organic compounds under light irradiation. Among various semiconductor photocatalysts, tungsten oxide (WO3) is one of the most promising candidates due to its advantages, including high stability, wide light adsorption range, proper band structures, and unique catalytic mechanism. This paper reviews the WO3-based materials for photocatalytic (PC) and photoelectrocatalytic (PEC) selective oxidations. We summarize the strategies for designing WO3 structures, which include morphology control, crystal facet optimization, and defect engineering. Then, the finely designed WO3 structures for PC and PEC oxidation of several typical organic compounds have been discussed based on catalytic mechanism and performance. Finally, we propose the prospects and challenges of WO3 photocatalysts and photoanodes in selective oxidation reactions.

DOI： 10.1002/cctc.202300723

Web of Science

Scopus

Publisher：Catalysis Letters  

The effect of sulfurization by SO2 on the activity of Pd/γ-Al2O3 for benzene oxidation was investigated. The activity decreased by heat treatment at 800 °C due to Pd particle coarsening. SO2 treatment at 600 °C suppressed the formation of byproduct compounds on the catalyst and improved the activity of the sintered Pd/γ-Al2O3 catalyst. Graphical Abstract: [Figure not available: see fulltext.]

DOI： 10.1007/s10562-022-04233-7

Web of Science

Scopus

Language：English   Publisher：Journal of Environmental Sciences (China)  

Non-thermal plasma (NTP) has been demonstrated as one of the promising technologies that can degrade volatile organic compounds (VOCs) under ambient condition. However, one of the key challenges of VOCs degradation in NTP is its relatively low mineralization rate, which needs to be addressed by introducing catalysts. Therefore, the design and optimization of catalysts have become the focus of NTP coupling catalysis research. In this work, a series of two-dimensional nanosheet Co-Ni metal oxides were synthesized by microwave method and investigated for the catalytic oxidation of benzene in an NTP-catalysis coupling system. Among them, Co2Ni1Ox achieves 60% carbon dioxide (CO2) selectivity (SCO2) when the benzene removal efficiency (REbenzene) reaches more than 99%, which is a significant enhancement compared with the CO2 selectivity obtained without any catalysts (38%) under the same input power. More intriguingly, this SCO2 is also significantly higher than that of single metal oxides, NiO or Co3O4, which is only around 40%. Such improved performance of this binary metal oxide catalyst is uniquely attributed to the synergistic effects of Co and Ni in Co2Ni1Ox catalyst. The introduction of Co2Ni1Ox was found to promote the generation of acrolein significantly, one of the key intermediates found in NTP alone system reported previously, suggest the benzene ring open reaction is promoted. Compared with monometallic oxides NiO and Co3O4, Co2Ni1Ox also shows higher active oxygen proportion, better oxygen mobility, and stronger low-temperature redox capability. The above factors result in the improved catalytic performance of Co2Ni1Ox in the NTP coupling removal of benzene.

DOI： 10.1016/j.jes.2022.09.030

Web of Science

Scopus

PubMed

Language：English   Publisher：Dalton Transactions  

Phenol is an important intermediate for manufacturing chemical products in industry. In recent decades, phenol synthesis by one-pot oxidation of benzene has aroused tremendous interest in phenol synthesis due to the enormous energy consumption of the three-step cumene method in the industry. Photocatalysis is promising for the selective conversion of benzene to phenol because it can proceed under mild reaction conditions. However, overoxidation of phenol by photocatalysts with high oxidation ability decreases the yield and selectivity, which is the major limiting factor. Thus, increasing the phenol formation efficiency plays a crucial role in photocatalytic systems for benzene oxidation. In this context, selective photocatalytic benzene oxidation over several types of photocatalytic systems has been developed rapidly in the past few years. In this perspective, current homogeneous and heterogeneous photocatalytic systems for this reaction have been reviewed systematically first. Then, an overview of some strategies from the last decade for increasing phenol selectivity has been provided. In the end, a summary and outlook on the challenges and future directions in the research field are included in this perspective, which would be of great interest for further improving the selectivity of the photocatalytic benzene oxidation reaction.

DOI： 10.1039/d3dt01360j

Scopus

PubMed

Publisher：Applied Catalysis B: Environmental  

Co-substituted Cu-Mn spinel oxides were synthesized, characterized, and catalytic performance for benzene oxidation was evaluated. Spinel phases, and the substitution of Mn sites by Co were confirmed for the ternary oxides. Co0.2Cu0.8MnOy showed the highest activities with the lowest apparent activation energy among the ternary oxides. The improved catalytic properties due to Co substitution are attributed to more activated lattice oxygen, stronger adsorption of benzene, and a larger specific surface area. Density functional theory simulations also revealed that the Co substitution enhanced the reactivity of the lattice oxygen. Adsorbed and activated benzene reacted with lattice oxygen to form abundant oxygen defects, which promoted O2 adsorption and dissociation, contributing to enhanced catalytic activity. The effect of water vapor on the catalytic benzene oxidation was also clarified.

DOI： 10.1016/j.apcatb.2022.122099

Web of Science

Scopus

Language：English   Publisher：Wiley  

CeO_2 and CeO_2-based materials are widely used as catalysts and catalyst supports for a variety of chemical reactions. The ability to form oxygen vacancies plays an important role in the catalytic activities in these materials. Therefore, revealing the reduction mechanism for CeO_2 is crucial to uderstanding the catalytic activities. In this study, shape-controlled CeO_2 nanoparticles are fabricated and the distribution of surface oxygen vacancies on the (100) and (111) surfaces is systematically studied using scanning transmission electron microscopy and electron energy-loss spectroscopy and the response to H_2 reduction treatment. It is successfully demonstrated that both catalytic activities and the ability to form oxygen vacancies are strongly dependent on the type of lattice planes. Moreover, the present results provide important insights into the reduction mechanism for CeO_2, in which bulk oxygen instead of the widely believed surface capping oxygen makes no small contribution to the initial reduction step.

DOI： 10.1002/admi.202201954

Web of Science

Scopus

CiNii Research

Publisher：Catalysis Today  

ABO3-type perovskite oxides containing transition metals at the B site are effective catalysts for oxidation reactions. In this study, LaNiO3 was prepared by the hydrolysis-precipitation method, and LaNiO3 was modified with Mn by the impregnation method. LaNiO3 showed higher CO oxidation activity than LaCoO3, LaMnO3, and LaFeO3. The high activity of LaNiO3 was attributed to the reactivity of the lattice oxygen in LaNiO3, as confirmed by temperature-programmed reduction by H2 (H2-TPR) and CO-TPR studies. The Mn-modified LaNiO3 exhibited higher activity for benzene oxidation than LaNiO3. The CO oxidation properties of the Mn-modified LaNiO3 catalysts correlated with their H2-reduction properties, whereas benzene oxidation properties were improved by the increasing amount of Mn on the catalyst surface.

DOI： 10.1016/j.cattod.2022.07.002

Web of Science

Scopus

Publisher：ACS Catalysis  

The photocatalytic oxidation of benzene to phenol driven by visible light (λ > 420 nm) at room temperature and under ambient pressure is a promising process. In particular, the application of heterogeneous catalysts to benzene photooxidation, where the catalyst and product are easily separated, facilitates the construction of practical processes. Here, we report that a Pt-loaded 1D monoclinic WO3nanorod (Pt/m-WNR) exhibited higher activities than other Pt/WO3catalysts with different crystal structures and morphologies in water under ambient conditions and visible light. Pt/m-WNR showed high stability in repeated reactions. Furthermore, other typical photocatalysts (TiO2, Bi2WO6, Bi2MoO6, BiOBr, and C3N4) showed negligible phenol formation using Pt as a cocatalyst. Both experimental results and density functional theory calculations show that the specific performance of Pt/m-WNR is due to the efficient reduction of O2to produce hydroxyl radicals via H2O2as an intermediate. Notably, m-WNR shows much higher phenol formation than h-WNR, although h-WNR has a higher surface area. The higher activity of m-WNR may be due to its lower work function to provide electrons for O2reduction. A lower work function will favorably form a higher Schottky barrier with Pt nanoparticles to suppress the recombination of photogenerated charge carriers. The effect of the Schottky barrier is further confirmed by different activities using various metal particles as cocatalysts.

DOI： 10.1021/acscatal.2c03832

Web of Science

Scopus

Publisher：Industrial and Engineering Chemistry Research  

Catalytic CO oxidation processes under dilute oxygen conditions are key industrial and environmental processes. CeO2-supported Pd and Pd-Cu catalysts (Pd/CeO2and Pd-Cu/CeO2) were prepared by impregnation, and the effect of Cu addition on the catalytic properties of CO oxidation was investigated under CO/O2stoichiometric conditions. The activity of Pd/CeO2was superior to that of Pd/TiO2and Pd/Al2O3at low temperatures. The Cu addition to Pd/CeO2with a Cu/Pd molar ratio of approximately 1-5 enhanced the CO oxidation activity. Small PdO particles were distributed over the CeO2surfaces, and Cu addition decreased the size of the Pd particles on the CeO2and increased the fraction of highly reactive Pd sites. As the Cu/Pd mole fraction in the Pd-Cu/CeO2catalyst increased to 10, the PdO on CeO2agglomerated significantly, and the CO oxidation activity decreased.

DOI： 10.1021/acs.iecr.2c02199

Web of Science

Scopus

Language：English   Publisher：Science  

A goal in the characterization of supported metal catalysts is to achieve particle-by-particle analysis of the charge state strongly correlated with the catalytic activity. Here, we demonstrate the direct identification of the charge state of individual platinum nanoparticles (NPs) supported on titanium dioxide using ultrahigh sensitivity and precision electron holography. Sophisticated phase-shift analysis for the part of the NPs protruding into the vacuum visualized slight potential changes around individual platinum NPs. The analysis revealed the number (only one to six electrons) and sense (positive or negative) of the charge per platinum NP. The underlying mechanism of platinum charging is explained by the work function differences between platinum and titanium dioxide (depending on the orientation relationship and lattice distortion) and by first-principles calculations in terms of the charge transfer processes.

DOI： 10.1126/science.abq5868

Web of Science

Scopus

PubMed

Publisher：Journal of Environmental Chemical Engineering  

Microwave-assisted process has been demonstrated to have immense potential for promoting chemical reactions and reducing energy consumption. In this study, catalytic oxidation of benzene was carried out over Co-Cu-Mn mixed oxides (CoxMn1-xCuOy) under microwave irradiation. The spinel-type mixed oxides were mainly formed for the Co-Cu-Mn mixed oxides with different Co/Mn ratios. The substitution of Mn sites by Co was confirmed by Fourier and Wavelet transformed extended x-ray absorption fine structure spectra. As the Co/Mn ratio increased, the heating characteristics of the catalysts under microwave irradiation monotonically improved. The benzene oxidation activity increased on the Co/Mn ratio of 2/3 due to the enhanced specific surface area, benzene adsorption properties, and lattice-oxygen reactivity. Microwave inducing significantly lowered the reaction temperature required for benzene oxidation. Co0.4Mn0.6CuOy completely oxidized benzene at a relatively low microwave power compared to pristine Cu-Mn oxides. The Co-Cu-Mn oxides showed high activity and stability for benzene oxidation even under humid conditions. Combining pre-adsorption and thermal oxidation processes on Co0.4Mn0.6CuOy improved the low concentration of benzene oxidation efficiency by rapid microwave heating. The compound of Co0.4Mn0.6CuOy and Co0.8Mn0.2CuOy mixed at 3:1 showed even higher activity than Co0.4Mn0.6CuOy.

DOI： 10.1016/j.jece.2022.108212

Web of Science

Scopus

Publisher：ACS Sustainable Chemistry and Engineering  

Catalytic hydrogenolysis is an efficient method for converting lignin-derived aryl ethers into monoaromatic products by cleaving the C-O bond and maintaining the phenyl rings. However, it is difficult to obtain aromatics with high selectivity because ring hydrogenation proceeds in parallel. Herein, we showed that a Cl-modified Pt/γ-Al2O3 catalyst exhibited higher selectivity for aromatics (91.6%) compared to unmodified Pt/γ-Al2O3 (3.9%) in C-O bond cleavage of diphenyl ether (DPE, 4-O-5 linkage in lignin). Characterization of the catalysts and density functional theory (DFT) calculations indicated that the Cl species preferred to localize at the terrace sites of Pt nanoparticles (NPs). Due to the decrease in the number of active sites, the Cl-modified Pt/γ-Al2O3 catalyst exhibited low activity for 2-propanol dehydrogenation, and thus the catalytic activity for the hydrogenation of aromatic products was suppressed. On the other hand, DPE adsorbed at the low coordination site, which caused the phenyl rings to move away from the metal surface; this configuration was unfavorable for the hydrogenation reaction. According to DFT calculations, the high selectivity for benzene was mainly attributed to the lower energy barrier for C-O bond cleavage of phenol at the low-coordination sites.

DOI： 10.1021/acssuschemeng.2c02038

Web of Science

Scopus

Language：English   Publisher：Environmental Science and Technology  

The Co3O4spinel is one of the most promising transition metal oxide (TMO) catalysts for volatile organic compound (VOC) treatment. Substituting effects have usually been utilized to improve the catalytic performance of the Co3O4spinel. In this study, Cu- and Ni-substituted Co3O4catalysts derived from mixed metal-organic frameworks (MMOFs) retained similar spinel structures but exhibited improved and reduced performance for o-xylene oxidation, respectively. Physicochemical characterization and DFT calculations revealed that Cu and Ni substitution into the Co3O4spinel varied the valence (Co3+/Co2+) and geometry (CoOh/CoTd) distributions of Co cations through different partial electron transfer and substitution sites. The higher Co3+/Co2+and CoOh/CoTdratios of the CuCo2O4catalyst contributed to the superior reducibility and oxygen mobility, which facilitated the oxidation of intermediates at lower temperatures in the catalytic oxidation of o-xylene. Meanwhile, the NiCo2O4catalyst with lower Co3+/Co2+and CoOh/CoTdratios could not completely oxidize intermediates under the same conditions due to inferior redox properties. Therefore, the CuCo2O4catalyst showed superior catalytic activity and stability to the NiCo2O4catalyst for the catalytic oxidation of o-xylene. This work provides insights into the synthesis of substituted Co3O4catalysts from MMOFs and mechanism of substituting effects, which might guide the design of efficient TMO catalysts for VOC treatment.

DOI： 10.1021/acs.est.2c02450

Web of Science

Scopus

PubMed

Publisher：ACS Applied Energy Materials  

Photocatalytic reactions to produce hydrogen from water under visible-light irradiation are an important key process for solar energy utilization. Because Cu-doped ZnS undergoes redox reactions upon irradiation with visible light, these materials have been applied to hydrogen production. In this study, Cu-doped ZnS catalysts were prepared by a solvothermal method, and their structures were investigated using scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and ultraviolet-visible spectroscopic studies. Cu-doped ZnS consists of nanospherical particles with a diameter of 50 nm. Cu2+ doping in ZnS causes structural distortion of the ZnS. The local structures were analyzed by X-ray absorption fine structure studies. As the amount of Cu added to ZnS increased, the degree of distortion of the ZnS structure also increased, and this degree of distortion reached a maximum when the Cu/Zn ratio was 0.07 (7% Cu doping). Cu-doped ZnS exhibited high activity in the hydrogen production reaction from water using Na2S and Na2SO3 as sacrificial agents under visible-light irradiation (λ > 420 nm), and the highest activity was observed at 7% Cu doping.

DOI： 10.1021/acsaem.1c03323

Web of Science

Scopus

Language：English   Publisher：Journal of Hazardous Materials  

Microwave-assisted heterogeneous catalytic oxidation of benzene was investigated over Cu-Mn spinel oxides. The spinel oxides were synthesized by a coprecipitation method from metal nitrate hydrolysis in a solution using tetramethylammonium hydroxide (TMAH) as a precipitation reagent. The catalysts were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, X-ray absorption fine structure, scanning electron microscopy, transmission electron microscope and H2-temperature-programmed reduction studies. Microwave absorption by the Cu-Mn spinel oxide is mainly driven by dielectric losses (dielectric heating). Cu-Mn spinel oxide with a Cu/Mn ratio of 1 exhibited superior activity to single oxides under microwave heating, demonstrating lower apparent activation energy than that obtained under conventional heating. Microwave irradiation lowered the reaction temperature required for benzene oxidation compared with conventional heating. Transient tests were used to investigate the reactivity of oxygen species in the catalytic reaction, and the high reactivity of Cu-Mn spinel oxides was related to the high reactivity of lattice oxygen on the catalyst surface. The reactivity of the oxygen species was enhanced under microwave heating, leading to an enhanced benzene oxidation reaction. The combination of adsorption and catalytic oxidation processes using Cu-Mn spinel oxides and zeolites efficiently decomposed benzene at low concentrations.

DOI： 10.1016/j.jhazmat.2021.127523

Web of Science

Scopus

PubMed

Publisher：Applied Physics Letters  

To enable better statistical analysis of catalyst nanoparticles by high-resolution electron holography, we improved the particle detection accuracy of our previously developed automated hologram acquisition system by using an image classifier trained with machine learning. The detection accuracy of 83% was achieved with the small training data of just 232 images showing nanoparticles by utilizing transfer learning based on VGG16 to train the image classifier. Although the construction of training data generally requires much effort, the time needed to select the training data candidates was significantly shortened by utilizing a pattern matching technique. Experimental results showed that the high-resolution hologram acquisition efficiency was improved by factors of about 100 and 6 compared to a scan method and a pattern-matching-only method, respectively.

DOI： 10.1063/5.0074231

Web of Science

Scopus

Language：Japanese   Publisher：The Japan Institute of Energy  

<p>Microwave irradiation accelerated hydrogen production by catalytic pyrolysis of crystalline cellulose and bamboo via Ni-SiO₂-Al₂O₃. The Debye-Waller factor measured by microwave in situ XAFS suggested that the reaction was accelerated due to the localized high temperature of Ni nanoparticles formed by microwave irradiation. We demonstrated that synergy of the microwave-enhanced pyrolysis of biomass and localized high temperature of Ni nanoparticles accelerate the catalytic pyrolysis of lignocellulose to produce hydrogen.</p>

DOI： 10.20550/jiebiomassronbun.17.0_29

CiNii Research

Language：English   Publisher：Nano Letters  

Understanding the nature of the interaction between a metal and support, which is known as the metal–support interaction, in supported metal catalysts is crucial to design catalysts with desired properties. Here, we have developed model Pt/TiO2 catalysts based on the deposition of colloidal Pt nanoparticles and studied their atomic and electronic structures before and after a postdeposition treatment that induces catalytic activity using aberration-corrected scanning transmission electron microscopy, electron energy loss spectroscopy, and first-principles calculations. Direct contact between Pt nanoparticles and TiO2 is realized after the postdeposition treatment, which is accompanied by the formation of a Ti3+ state on the TiO2 surface close to the Pt nanoparticles and a Ptδ+ state on the Pt nanoparticles. The origin of these two states and their effect on the catalytic properties are discussed. These findings pave the way for a comprehensive understanding of metal–support interactions in supported metal catalysts.

DOI： 10.1021/acs.nanolett.1c03485

Web of Science

Scopus

PubMed

Publisher：Chemical Engineering Journal  

The synthesis of phenol by one-pot oxidation of benzene with dioxygen (O2) is a significant conceptual and practical challenge because benzene has low reactivity to O2 at room temperature and ambient pressure. Furthermore, phenol is more reactive than benzene and is easily overoxidized, so complete oxidation is more likely to proceed in the benzene oxidation reaction, which generally results in lower phenol yield and selectivity. Herein, we report that a heteropolyacid H3PW12O40 functions as a photocatalyst for benzene oxidation reaction in an aqueous acetonitrile solution using O2 in high phenol yield (23–41%) and selectivity (80–90%). The addition of acetonitrile to the reaction solution significantly inhibited the complexation between phenol and H3PW12O40, preventing phenol overoxidation. Furthermore, no decomposition of H3PW12O40 during the reaction was evidenced by UV–VIS spectra. This photocatalyst can be used repeatedly with only a slight decrease in the rate of phenol formation. For the mechanistic study, the initial rates, which depended on the reaction conditions, were investigated in detail. The benzene oxidation under anaerobic conditions was also conducted as a control experiment. A color change of reaction solution from colorless to blue has confirmed the reduction of H3PW12O40 during the catalytic process and the formation of reduced H3PW12O40 detected in the UV–VIS spectra. A kinetic isotope effect (KIE), kH/kD = 1.15, is found for the oxidation of benzene/benzene‑d6, indicating electron transfer is the principal C−H bond activation process in the mechanism. We identified hydrogen peroxide as an intermediate and found that phenol was generated in both the photocatalytic reduction and reoxidation process in our system.

DOI： 10.1016/j.cej.2021.131369

Web of Science

Scopus

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Modifying photocatalyst with defects offers effective pathway to tailor light absorption properties, but may result in more sluggish kinetics. Therefore, enhanced light absorption often could not guarantee increased activity. Here, we report a dual defect strategy to extend light absorption with minimal loss in charge dynamics. Fine-tuned amount of dual defect, i.e., nitrogen defects and single-site copper, is simultaneously generated in polymer carbon nitride(PCN) through in-situ vapor diffusion method. Surface nitrogen defect extends the light absorption to long-wavelength via sub-band absorption. The interaction between nitrogen and single-site copper at certain concentration retains the charge dynamics by making the photogenerated electrons more delocalized through the newly-formed copper-nitrogen bonds. As a result, champion modified PCN exhibits robust hydrogen production activity, roughly 4.5-fold greater than the pristine counterpart in both visible and full light ranges. More intriguingly, this synergism provides PCN with efficient visible light activity even in faint tailing optical absorption region(>450 nm).

DOI： 10.1016/j.apcatb.2020.119099

Language：English   Publishing type：Research paper (scientific journal)  

BACKGROUND: Benzene (C₆H₆) is a typical kind of volatile organic compound (VOC) which can exert great harm to both human health and the environment, and, thus, which needs to be eliminated before its emission. In this work, porous manganese–nickel (Mn-Ni) composite oxide catalysts were synthesized through the oxalate route and applied to thermal catalytic oxidation of C₆H₆. By means of activity tests and relative physico-chemical characterizations, the factors affecting the activity of those Mn-Ni composite oxides were explored. RESULTS: Nitrogen (N₂)-adsorption/desorption and X-ray photoelectron spectroscopy (XPS) measurements indicated that the Brunauer–Elmett–Teller (BET) surface area and the content of surface-adsorbed oxygen species were increased due to the addition of Ni into Mn oxide (MnO_x). Meanwhile, the oxygen mobility and reducibility also were improved in the Mn-Ni composite oxides. Accordingly, compared with MnO_x, the Mn-Ni catalysts showed higher activity for thermal catalytic oxidation of C₆H₆. Moreover, porous Mn-Ni composite oxides with a Mn:Ni molar ratio of 4:1 (Mn4Ni1) displayed the best catalytic activity. Further investigation indicated that the excellent catalytic performance of Mn4Ni1 composite oxides could be ascribed mainly to the larger BET surface area and the richer content of surface-adsorbed oxygen species, as well as stronger oxygen mobility and better reducibility compared with other Mn-Ni catalysts. CONCLUSIONS: The Mn4Ni1 composite oxides showed a lowest T₉₀ value of 172 °C (C₆H₆ concentration 200 ppm, WHSV 60 000 mL g⁻¹ h⁻¹) among all of the obtained Mn-Ni composite oxides. Moreover, it also exhibited favourable catalytic stability at 210 °C in the presence or absence of moisture.

DOI： 10.1002/jctb.6280

Language：English   Publishing type：Research paper (scientific journal)  

Pt/TiO₂ microspheres with sea-urchin like structures were prepared by sequential processes including the preparation of TiO₂ by a hydrothermal method and the preheating of the TiO₂, the deposition of Pt nanoparticles on the TiO₂ surface, followed by post heating in O₂/N₂ and H₂. The TiO₂ and Pt/TiO₂ catalysts were characterized by XRD, Raman, SEM, TEM and N₂ adsorption studies. The average diameter of TiO₂ microspheres was about 250 nm. The TiO₂ microspheres were composed of TiO₂ nanoparticles with the size of 20−30 nm. Pt particles with the size of 3 nm were highly dispersed on the TiO₂ microsphere by liquid phase adsorption of colloidal Pt particles. The heating of TiO₂ at 300 °C before and after the Pt deposition did not change the size of TiO₂ microsphere and reduced the surface area from 238 to 137 m² g⁻¹. The Pt/TiO₂ microsphere exhibited higher catalytic activity for benzene oxidation than Pt/TiO₂ P25 under normal outer heating, whereas pristine TiO₂ exhibited almost no activity. Activated carbon was used as a catalyst with a mixture of Pt/TiO₂ microspheres when performing the catalytic reaction under microwave heating. The mixture of Pt/TiO₂ and activated carbon showed higher benzene oxidation activity under microwave irradiation than under normal external heating. The mixture was applied to benzene adsorption-catalytic oxidation combined processes.

DOI： 10.1016/j.cattod.2020.05.021

Language：English   Publishing type：Research paper (scientific journal)  

This study aimed to investigate the effect of carbon derived from glucose (C) on the physicochemical characteristics and catalytic activity of Ni, supported over SiO₂, ZSM-5, and TiO₂ in methane dry reforming. Among the Ni catalysts without C, Ni/SiO₂ exhibited the highest CH₄-CO₂ conversion and stability at all experimented temperatures. On the other hand, the C-incorporated catalysts prepared by glucose impregnation, followed by pyrolysis, showed dissimilar performances. C improved the stability of Ni/SiO₂ in the reforming at 650^◦C and 750^◦C and increased the CH₄ and CO₂ conversion to the level close to the thermodynamic equilibrium at 850^◦C. However, this element did not substantially affect the activity of Ni/ZSM-5 and exerted a retarding effect on Ni/TiO₂. Characterizations with H₂-TPD, XRD, EXAFS, and STEM-EDS revealed that the different influences of C by the supports were attributed to the extent of metal dispersion and metal-support interaction.

DOI： 10.3390/catal10010021

Language：English   Publishing type：Research paper (scientific journal)  

Plasma-catalysis system comprising surface discharge reactor (SDR)and catalysts were constructed and tested for benzene decomposition. In benzene oxidation with SDR, benzene conversion and the amount of COx formed monotonically increased with input energy, but the benzene decomposition behavior was not related with ozone formation. The loading of metal oxides, Al₂O₃, TiO₂ and CeO₂ in SDR greatly promoted benzene oxidation and CO₂ formation. The highest activity was obtained with manganese oxides dispersed on ultrastable zeolite Y (Mn/USY). In the range of low input power, the amount of ozone formed increased with the input power, and ozone can be efficiently consumed in benzene oxidation by loading the Mn/USY catalyst in the latter part of SDR. In the higher power range where the amount of ozone decreased with increasing the power, the loading of Mn/USY catalyst inside the reactor was more effective because not only ozone but also short-lived species formed in SDR were utilized for benzene oxidation. The addition of water vapor to reaction gas did not affect benzene conversion and COx formation with SDR-Mn/USY catalyst system. The preadsorbed benzene on the Mn/USY catalyst can be oxidized to CO₂ with high selectivity compared with homogeneous oxidation of benzene in SDR.

DOI： 10.1016/j.cattod.2018.07.055

Language：English   Publishing type：Research paper (scientific journal)  

Background: Formaldehyde (HCHO) and ozone (O₃) are seriously hazardous materials to human health, especially in the indoor environment, and need to be inhibited. Manganese dioxide (MnO₂) catalysts have been extensively studied in the field of environmental pollution owing to their various morphologies and crystal structures. In this study, one-dimensional rod-like MnO₂ catalysts were prepared by a hydrothermal method. The crystal form and other factors affecting the activity were explored through an activity test and various characterization methods. The decomposition process of HCHO and O₃ on the most active catalyst was analyzed by in situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). Results: α-MnO₂ displayed the best catalytic performance and achieved 90% HCHO conversion, 100% carbon dioxide (CO₂) yield and 100% O₃ decomposition under different experimental conditions. The characterization results illustrated that the crystal phase of α-MnO₂ has a suitable tunnel structure for HCHO adsorption, also leading to greater mobility of adsorbed oxygen species, abundant oxygen vacancies and active surface oxygen species, which could be the reason for the superior catalytic performance of α-MnO₂. Formate and dioxymethylene (DOM) species were identified as the dominant intermediates by in situ DRIFTS. The surface hydroxyl (OH) group was confirmed to play an essential role in the complete oxidation of carbonaceous intermediates into harmless CO₂ and water (H₂O). Conclusion: α-MnO₂ exhibited the best catalytic performance among the as-prepared samples and can efficiently eliminate HCHO and O₃ in the environment.

DOI： 10.1002/jctb.6023

Language：English   Publishing type：Research paper (scientific journal)  

The deactivation of noble metal catalysts by SO
₂
and H
₂
O is a common issue in the post combustion treatment of flue gases from sintering processes in the steel industry. In an effort to develop SO
₂
-tolerant CO-oxidation catalysts, herein, we investigated the effect of SO
₂
and H
₂
O on the catalytic activity of Pt/TiO
₂
(P-25) catalysts for CO oxidation using X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), and diffuse-reflectance infrared Fourier-transform (DRIFT) spectroscopy. Pt/TiO
₂
(P-25) catalysts, in the absence of SO
₂
and presence of H
₂
O, enhanced the activity and stability of CO oxidation, while being largely suppressed and irreversibly deactivated in the presences of SO
₂
. The XPS and TEM results suggested that variations in the Pt particle size and oxidation state were not major causes of the deactivation. Instead, according to DRIFT spectra, the interaction between CO and H
₂
O at the metal-support interface was weakened after the formation of TiOSO
₄
on the TiO
₂
surface in the presence of SO
₂
. This resulted in a loss of the previously observed enhancement of CO oxidation under humid conditions. These results indicate that in the presence of SO
₂
, the formation of TiOSO
₄
is the major cause of irreversible deactivation. Therefore, removal of the TiOSO
₄
layer from the TiO
₂
surface is a crucial step for catalyst regeneration. Graphical Abstract: [Figure not available: see fulltext.].

DOI： 10.1007/s10562-019-02672-3

Language：English   Publishing type：Research paper (scientific journal)  

Three manganese oxide catalysts (MnO
_x
) were synthesized via a simple method, and then they were introduced into the non-thermal plasma (NTP) system for benzene removal. The XRD and EXAFS results showed the MnO
_x
were mainly in the Mn
₃
O
₄
phase, and from the analysis of N
₂
adsorption/desorption isotherms, we knew the MnO
_x
calcined at 250 °C (Mn250) had the largest surface area of 274.5 m
²
 g
⁻¹
. Besides, Mn250 also exerted higher benzene adsorption capacity (0.430 mmol g
⁻¹
) according to C
₆
H
₆
-TPD. O
₂
-TPD indicated that Mn250 showed better oxygen mobility than Mn300. Moreover, by analyzing XPS results, it revealed that Mn250 exhibited rich abundant of surface adsorbed oxygen species (O
_ads
) and moderate ratio of Mn
⁴⁺
/Mn
³⁺
, and the reducibility temperature was also the lowest among all the MnO
_x
catalysts drawn by H
₂
-TPR profiles. As a result, Mn250 combined with NTP could remove 96.9% of benzene at a low input power of 3 W (benzene concentration 200 ppm, and GHSV 60,000 mL g
_cat.

⁻¹
 h
⁻¹
), performing the best catalytic activity among the three catalysts and plasma only. Furthermore, the “NTP + Mn250” system also produced the highest CO
₂
concentration and lowest CO concentration in downstream, and the residual O
₃
after catalytic reaction was also the lowest, that is to say, the synergistic effect between NTP and Mn250 was more effective than other catalysts in benzene removal. [Figure not available: see fulltext.].

DOI： 10.1007/s11356-019-04264-5

Language：English   Publishing type：Research paper (scientific journal)  

Series of MnO
_x
catalysts were synthesized through oxalate route and calcined at facile temperatures. Characterizations through XRD, N
₂
-adsorption/desorption, HRTEM, C
₆
H
₆
-TPD, O
₂
-TPD, XPS, and H
₂
-TPR revealed that MnO
_x
calcined at 250 °C (N250) with a main crystal phase of Mn
₂
O
₃
showed micro-mesopores and largest specific surface area, and therefore had a high adsorption capacity of C
₆
H
₆
. N250 also presented better oxygen mobility, rich surface adsorbed oxygen species (O
_ads
), and proper ratio of surface Mn
⁴⁺
/Mn
³⁺
. The starting temperature of H
₂
-TPR of N250 was the lowest among the obtained MnO
_x
samples. As a result, N250 exhibited the lowest T
₉₀
value of 191 °C in C
₆
H
₆
thermal catalytic oxidation (WHSV 60,000 mL g
_cat
.
⁻¹
 h
⁻¹
, initial C
₆
H
₆
concentration 190 ppm) among all the catalysts, and this T
₉₀
value is lower than those reported in many research. At last, a potential reaction pathway was proposed according to the results of in-situ FTIR measurement.

DOI： 10.1007/s10563-019-09268-2

Language：English   Publishing type：Research paper (scientific journal)  

The room-temperature oxidation of CO using ozone-assisted catalysis (OAC) over monometallic or bimetallic catalysts supported on γ-Al₂O₃ is presented. Within the tested particle size range, ozone decomposition was insensitive to the size of the Ag particles (6.6–11.9 nm) at weight hourly space velocities of up to 360 L·g⁻¹·h⁻¹. Among the tested monometallic catalysts (Ag Pd, Fe, Mn, and Cu), Ag showed the highest activity for CO oxidation. Bimetallic catalysts (Ag-M or Pd-M where M = Cu, La, Ru, and Fe) were also considered by adding a second metal or perovskite oxide (LaFeO₃) to Ag. A cooperative effect was observed with the bimetallic Ag-Pd catalyst for the OAC of CO oxidation at room temperature, whereas the other bimetallic catalysts showed slightly lower performance compared to the monometallic catalyst. A high ozone utilization efficiency of 0.94 was achieved with the bimetallic Ag-Pd/γ-Al₂O₃ catalyst. High-angle annular dark-field scanning tunneling electron microscopy (HAADF) and energy dispersive X-ray (EDX) spectroscopy measurements confirmed the proximity of the two components, which is essential for their interaction. The in situ FTIR measurements revealed that the cooperative effect in the bimetallic Ag-Pd catalyst involved modification of CO adsorption and the suppression of product accumulation. Two typical IR absorption bands of linear- (2090 cm⁻¹) and bridge-CO (1918 cm⁻¹) on Pd disappeared in the presence of Ag nanoparticles. Thus, the presence of Ag in contact with Pd inhibited the accumulation of carbonates, which led to enhanced catalytic performance. Adsorption site-dependent CO oxidation on Pd was also confirmed by the in situ Fourier transform IR measurement.

DOI： 10.1016/j.cej.2018.08.159

Language：English   Publishing type：Research paper (scientific journal)  

Benzene is a harmful material that must be to be removed from flue gases. In this study, the performance of a surface discharge plasma-catalysis combined reactor for benzene decomposition was studied. Benzene conversion and CO₂ selectivity increased upon loading a CeO₂ catalyst onto the plasma reactor. The conversion and selectivity depended on the surface area of the CeO₂. FTIR studies revealed that byproduct organic compounds are formed on the CeO₂, confirming that benzene oxidation occurs on the CeO₂ catalysts.

DOI： 10.5109/1957498

Language：English   Publishing type：Research paper (scientific journal)  

The catalytic combustion of soot and CO is one of the key technologies required to meet rigorous emission standards. Recently, solid solution materials have been employed in heterogeneous catalysts because of their remarkable intrinsic activities and good stabilities. However, the low number of contact points between soot particles and the catalyst remains a challenge to enhancing catalytic performance. Thus, we herein report the preparation of Ce-ZrO₂ solid solution nano-fibrous web catalysts with a hierarchical structure using an electrospinning method, where Ag particles were loaded onto the surface of the Ce-ZrO₂ webs. X-ray diffraction, scanning transmission electron microscopy, and energy dispersive spectroscopic studies allowed us to investigate the morphological and crystal structures of the prepared Ce-ZrO₂ and Ag/Ce-ZrO₂ web catalysts. Moreover, the relationship between the Ce/Zr ratio and activated oxygen is discussed based on X-ray photoelectron spectroscopy results. Following the catalytic oxidation of soot and CO using our novel materials, we found that the Ce_0.67Zr_0.33O₂ web exhibited higher catalytic activities than the Ce_0.5Zr_0.5O₂ and Ce_0.33Zr_0.67O₂ webs, respectively. In addition, Ag/Ce_0.67Zr_0.33O₂ exhibited enhanced catalytic activity compared with the pristine Ce_0.67Zr_0.33O₂ for the oxidation of both soot (e.g., 500 °C vs. 544 °C at 50% conversion) and CO (e.g., 282 °C vs. 408 °C at 50% conversion). It therefore appeared that our proposed Ce-ZrO₂ solid solution nano-fibrous web catalysts bearing Ag particles exhibited superior redox properties and enhanced surface areas, and as such, are promising candidates for use in the oxidation of both soot and CO.

DOI： 10.1016/j.fuel.2017.10.007

Language：English   Publishing type：Research paper (scientific journal)  

The TiO₂(P25)-supported Pt catalyst has drawn significant interest from researchers due to its high activity. Analysis of the origin of this high catalytic activity must address the heterogeneity of the catalyst, since TiO₂(P25) comprises both anatase and rutile phases. Thus, in this study, we demonstrate a simple method for determining the ratio of Pt particles on anatase and rutile by X-ray diffraction and transmission electron microscopy, without employing special equipment. Such a cost-effective method for determining the Pt distribution will accelerate research into the use of TiO₂(P25) as a catalyst support.

DOI： 10.5109/2174853

Language：English   Publishing type：Research paper (scientific journal)  

A sulfur dioxide (SO₂)-tolerant, stable mixed oxide as an alternative to platinum (Pt) group metal (PGM) catalysts has been explored for the catalytic oxidation of particulate matter (PM) due to its low-cost, desirable physiochemical properties, thermal stability, tailoring options, etc. Herein, a mixed oxide of Sr and Cr was prepared via a solution combustion method by mixing stoichiometric amounts of Sr- and Cr-precursors with citric acid and urea as fuels followed by calcination at 800 °C in air. A pure mixed oxide phase of Sr and Cr (SrCrO₄) (P2₁/n [14]) (a = 0.7090 nm, b = 0.7394 nm, and c = 0.6755 nm) has been successfully prepared, and the SrCrO₄ particles are larger in size with semi-oval shapes due to their agglomeration at elevated temperatures. The SrCrO₄ catalyst shows significantly improved intrinsic catalytic performance for PM oxidation in the tested temperature range as compared to the reference catalysts, Pt/Al₂O₃ and Pt-dispersed SrCrO₄ (Pt/SrCrO₄) (loading weight: 5 wt%) are used as internal reference catalysts. The onset temperature (i.e., intrinsic catalytic activity at 10% conversion, T₁₀) is observed at 426 °C, which is significantly lower than that of the reference Pt/Al₂O₃ (T₁₀ = 537 °C) and comparable with that of the Pt/SrCrO₄ catalyst (T₁₀ = 414 °C). The SrCrO₄ catalyst shows a stable, multi-cycle PM oxidation performance for the tested five cycles, and both its crystalline structure and morphology remain unchanged even after its multiple cycles of use. The structure of the SrCrO₄ catalyst is stable even after moisture and SO₂ treatments, and the catalytic PM oxidation activity of SrCrO₄ is not compromised even after these harsh treatments. Importantly, the SrCrO₄ catalyst is also stable after PM oxidation conducted using real world PM from a heavy-duty vehicle. These results demonstrate that the mixed oxide phase of SrCrO₄ shows promise for PM oxidation.

DOI： 10.1039/c7cy02553j

Language：English   Publishing type：Research paper (scientific journal)  

Manganese cerium oxides were synthesized by Pechini method and were used for investigating the performance of solid solution and the influence of water vapor presence on catalytic decomposition of formaldehyde and ozone at room temperature. Compared with the pristine manganese oxides and cerium dioxide, MnCeOx catalyst exhibited the best performance on HCHO oxidation and excellent ozone decomposition under dry air conditions although the CO₂ yield is much lower than that of the solo cerium oxide. The as-prepared catalysts were characterized by XRD, XPS, N₂ adsorption-desorption, H₂-TPR and O₂-TPD techniques. These characterization results revealed that the MnCeO_x catalyst formed a solid solution of manganese and cerium, and exhibited relatively abundance oxygen vacancies and the most surface lattice oxygen species, enhancing remarkable adsorption and redox properties. MnCeO_x catalyst has ∼100% HCHO conversion into CO₂ in the catalytic activity test while the relative humidity is higher than 50% in this work, which could be suitable for indoor air purification. In situ DRIFTS results demonstrated that this excellent performance of HCHO complete oxidation is attributed to the continuously replenished surface hydroxyl groups generated from the interaction of water vapor and ozone on the surface of MnCeO_x catalyst. This composite oxide is a promising catalyst for removing formaldehyde and ozone in the indoor environment.

DOI： 10.1016/j.cattod.2018.04.027

Language：English   Publishing type：Research paper (scientific journal)  

An Aquivion/titanium zirconium oxide nanofibrous web composite membrane was prepared and tested as a proton exchange membrane in a hydrogen/air fuel cell. The incorporation of a small dose (9 wt % membrane) of a uniformly distributed electrospun titanium zirconium oxide (TiO₂/ZrO₂; Ti/Zr = 1:1 atomic ratio) nanofibrous web significantly improved hydromechanical stability of the composite membranes, which exhibited approximately 2 times higher water retention and 30 times lower dimensional change than a pristine Aquivion membrane under in-water membrane hydration conditions. Phosphate functionalities were successfully added onto the nanofiber surface, as confirmed by X-ray photoelectron spectroscopy (XPS) analysis. The added phosphate functionality resulted in higher proton conductivity of the prepared composite membrane compared to the non-modified TiO₂/ZrO₂ nanofibrous web composite membrane [e.g., 0.027 S cm^-1 versus 0.021 S cm^-1 at 120°C and 40% relative humidity (RH)]. A single cell test also showed the effect of an added TiO₂/ZrO₂ nanofibrous web. A single cell with an Aquivion/TiO₂/ZrO₂ nanofibrous web composite membrane outperformed a single cell with a pristine Aquivion membrane in fully humidified conditions (100% RH at 75 and 90°C). The Aquivion/phosphate-modified TiO₂/ZrO₂ nanofibrous web composite membrane showed the best single cell performance at all four testing conditions, including the fully humidified medium-temperature conditions (e.g., P_max = 1.18 W cm^-2 at 75°C and 100% RH, and P_max = 0.97 W cm^-2 at 90°C and 100% RH) and partially humidified high-temperature conditions (P_max = 0.45 W cm^-2 at 120°C and 40% RH, and P_max = 0.21 W cm^-2 at 140°C and 20% RH). The composite membrane also displayed excellent durability evidenced by the accelerated lifetime (ALT) test results. Overall, the phosphate-modified TiO₂/ZrO₂ nanofibrous web composite membrane enhanced the electrical properties and durability of the fuel cell, especially at high temperatures (>120°C).

DOI： 10.1021/acs.energyfuels.7b00941

Language：English   Publishing type：Research paper (scientific journal)  

Mesoporous zirconia (ZrO₂) nanofibers were synthesized by an electrospinning method and calcination at 600 °C. Ag and Mn oxides were separately or simultaneously deposited on the ZrO₂ nanofibers by impregnation methods. The structure of the ZrO₂ supported nanofiber materials were examined by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS). Ag and Mn oxides were homogeneously deposited on the surface of ZrO₂ nanofibers. Metallic Ag species and Mn₂O₃ were formed on the ZrO₂ nanofibers when they were separately deposited, whereas the codeposition of Ag and Mn changed the oxidation state of Mn oxides on the catalyst surface. The supported catalysts were evaluated for their soot and benzene oxidation performance. The co-deposition of Ag and Mn lowered the light-off temperature for benzene oxidation. The soot oxidation performance was comparable for the Ag/ZrO₂, Mn/ZrO₂ and Ag-Mn/ZrO₂ catalysts under tight contact mode, whereas Ag/ZrO₂ exhibited the highest activity and the activity decreased with decreasing the Ag content under loose contact mode.

DOI： 10.1016/j.cattod.2016.05.050

Language：English   Publishing type：Research paper (scientific journal)  

A novel synthesis of morphology-controlled perovskite networked with LaCr_0.8Ru_0.2O₃ nanoparticles was introduced using activated carbons as sacrificial templates. These catalysts were used for the hydrogen production by heavy-hydrocarbon autothermal reforming. To investigate the effect of the carbon templates, morphology-controlled perovskites using activated carbons and a non-templated catalyst were prepared to determine how carbon templates influence the chemical structure of the perovskite. The carbon templates produced a crystalline structure with the well incorporation of Ru under mild calcination conditions. The morphology of the hollow fibers provided a higher specific surface area than that of the porous grain catalyst with a similar average particle size (∼80 nm). It was found that the hollow fibers showed a unique pore structure with large macropores from 1 to 100 μm, which might offer a higher surface area and enhanced mass transfer of the reactants. This provided a higher activation energy for H₂ production than the porous grain and non-templated catalysts during the autothermal reforming of heavy hydrocarbons. As a result, the fibrous feature and well-defined chemical structure were crucial factors when cracking the hydrocarbon chain. The hollow fiber catalyst showed high reforming efficiency for H₂ production (>65 mol%) from heavy-hydrocarbon fuels during long-term experiments, featuring substantial durability with low carbon deposition and no structural changes.

DOI： 10.1016/j.fuel.2016.09.065

Language：English   Publishing type：Research paper (scientific journal)  

This paper reports, for the first time, complete arene hydrogenation of phenolic compounds as lignin monomers over a non-noble metal catalyst supported by a general material. A type of nano-sized Ni catalyst was prepared in ethanol and in situ supported by ZSM-5 zeolite through general borohydride reduction of Ni²⁺ to Ni⁰, but with application of a simple ligand, pyridine. This catalyst showed an activity so high as to completely or near completely hydrogenate the aromatic rings of phenol and its twelve derivatives as potential lignin monomers at 180 °C. The activity was clearly higher than that of another type of conventional Ni catalyst prepared in the absence of pyridine. Analyses of the catalysts by TEM/EDS, XPS, XAFS and others demonstrated that pyridine had crucial roles in selective formation of nano-sized Ni and maintenance of its activity by appropriate interaction with the support. This paper also shows our theoretical approach to the mechanism of the borohydride reduction. First-principles calculations based on density functional theory (DFT) revealed the reaction pathway from Ni²⁺ to Ni⁰ and the role of pyridine, which was validated by some experimental facts. The DFT calculations also explain the variety of reactivities of the lignin monomers, which are strongly influenced by their molecular electrostatic and steric nature.

DOI： 10.1039/c6ta08538e

Language：English   Publishing type：Research paper (scientific journal)  

Abstract: CeO₂-supported LaMnO₃ perovskite oxides were prepared to study their catalytic properties in the oxidation of NO to NO₂. To prepare the catalyst and investigate the interaction between LaMnO₃ and CeO₂, two deposition methods were used. Extended X-ray absorption fine structure studies confirmed that perovskite oxide phases were formed on the CeO₂ support. Moreover, X-ray photoelectron spectroscopy and temperature-programmed reduction with H₂ studies revealed that the reduction temperatures for perovskite oxides and CeO₂ support decreased by the deposition followed by calcination at 650 °C, and that the interaction between the LaMnO₃ and CeO₂ support can be controlled by changing the preparation method. The LaMnO₃/CeO₂ catalyst in which LaMnO₃ was highly dispersed on CeO₂ exhibited higher NO oxidation activity than either LaMnO₃ or CeO₂. The thermal stability of the LaMnO₃/CeO₂ catalyst was compared with that of alumina-supported LaMnO₃ catalysts over 850–1050 °C. Graphical Abstract: [Figure not available: see fulltext.]

DOI： 10.1007/s10562-016-1878-3

Language：English   Publishing type：Research paper (scientific journal)  

We developed a new technique for mitigating catalyst deactivation caused by SO₂ in exhaust gases. A series of 0.1 wt %-Pt/TiO₂ catalysts with different surface, crystal, and pore structures were prepared and tested for CO oxidation activity in the presence of SO₂ and H₂O. The order of the CO oxidation activity under the influence of SO₂ was much different from that in the absence of SO₂. Catalysts with a high ratio of larger pores exhibited higher catalytic activity under the influence of SO₂ and H₂O in the temperature range of 250-300 °C, whereas other parameters, such as BET surface area and crystal structure of the TiO₂ support, had minor effects on the CO oxidation activity. The oxidation state of Pt differed significantly depending on the kind of TiO₂ support. Some catalysts were less active without H₂ reduction pretreatment due to the presence of oxidized Pt species.

DOI： 10.1021/acs.est.6b01652

Language：English   Publishing type：Research paper (scientific journal)  

Perovskite-type oxides have been widely applied in heterogeneous catalytic reactions, such as soot oxidation. However, a poor contact point between the catalyst and solid reactant (soot) often limits the catalytic performance. Here, we report La_{1 - x}Sr_xCo_0.2Fe_0.8O_{3 - δ} perovskite oxide catalysts with a unique three-dimensional (3D) fiber web structure that increases the high-contact area by trapping soot in the unique pore structure for effective catalytic activity. This feature was carefully analyzed using scanning transmission electron microscopy (STEM) tomography to investigate the location of the soot on the web. The structure of the web, with a thickness of approximately 55 μm, indicated that the soot particles were caught by the 3D pores between the fibers. The relationship between the Sr amount and activate oxygen was also characterized by means of XPS. The results show that the Sr amount of 0.4 produced the highest amount of active oxygen species (O^-) that are essential for soot oxidation reaction. The developed catalyst exhibited a good catalytic performance due to the optimized perovskite chemical structure and the greatly increased number of the contact points owing to the 3D inter-fiber spaces. Hence, our proposed approach is reasonable for application to real soot combustion processes and can also be easily extended to numerous other catalytic processes to enhance the catalytic activity.

DOI： 10.1016/j.apcatb.2016.03.001

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1007/s11144-016-0974-0

Language：Japanese   Publishing type：Research paper (scientific journal)  

Repository Public URL： https://hdl.handle.net/2324/1560666

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1246/bcsj.20150186

Language：English   Publishing type：Research paper (scientific journal)  

Ceria oxide (CeO₂) nanofibers with diameters of 241-253nm were produced via the electrospinning method. They were then applied as new support materials for silver nanoparticles and their effectiveness as diesel soot oxidation catalysts was examined. The crystal structure of the Ag was confirmed by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscopy (HR-TEM), and energy dispersive spectroscopy (EDS). The diesel soot oxidation experiment was performed using a mixture of carbon black and the fabricated catalyst. In the tight contact and loose contact modes, the highest temperatures of both the CeO₂-fiber-supported Ag catalysts (Ag/CeO₂) calcined at 500°C and the CeO₂ fibers calcined at 500°C were shifted to a lower temperature range, compared with JRC-CEO-3 (a commercial catalyst). In addition, the activation energy also showed similar behavior. Thus, the fibrous CeO₂ and Ag/CeO₂ have been shown to be effective and promising catalysts for soot oxidation.

DOI： 10.1016/j.apcatb.2015.03.008

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1246/bcsj.20150111

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.fuproc.2014.10.002

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1016/j.cattod.2014.09.033

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Catalytic oxidation of gaseous benzene using ozone over SiO₂-supported metal oxides (oxides of Mn, Fe, Co, Ni, and Cu) was performed at 343 K. The supported metal oxides were prepared from metal nitrates via impregnation followed by calcination at 873 K. X-ray diffraction studies revealed that aggregated metal oxides were formed on the supports. The quantities of the exposed metal oxides on SiO₂ were determined using temperature-programmed desorption of formic acid species adsorbed on the catalysts. The turnover frequencies (TOFs) for ozone decomposition and catalytic oxidation of benzene with ozone were also compared for the supported metal oxides. The TOFs for ozone decomposition with the supported metal oxides decreased in the order: Cu > Co ~ Ni > Fe > Mn. Conversely, the SiO₂-supported Mn oxide (Mn/SiO₂) catalyst exhibited the highest activity for catalytic oxidation of benzene with ozone and the highest efficiency for ozone utilization. FTIR studies revealed that benzene ring cleavage continuously proceeded on the Mn/SiO₂ catalyst, and oxygen-containing species, which were readily oxidized to CO₂ and CO in the presence of ozone, accumulated on the catalyst surface. The Fe-, Co-, Ni-, and Cu-oxides suffered from catalyst deactivation due to the build-up of by-product compounds, which was attributed to their low activity for oxidation of these substances. These results suggest that the most important steps in benzene oxidation with ozone on metal oxides are the formation and oxidation of by-product compounds. The higher activity of the Mn oxide catalyst for benzene oxidation is ascribed to the facile oxidation of these by-product compounds.

DOI： 10.1039/c5cy00315f

Language：English   Publishing type：Research paper (scientific journal)  

Mechanochemical modification of previously synthesized LaFeO₃ perovskite-type oxide by a high-energy ball milling was investigated to introduce Fe⁴⁺ ions or transform some Fe³⁺ into Fe⁴⁺ in LaFeO₃. X-ray absorption fine structure studies revealed that the formation of Fe⁴⁺ ions into LaFeO₃ perovskite has been achieved at first time by ball milling at room temperature without any additives or replacement of La³⁺ ions by some divalent cations. The structural model of Fe⁴⁺ containing LaFeO₃ could be described as with a modified perovskite having equal amounts of La and Fe vacancies, which is supported by a good correlation between the results of Fe K-edge XANES spectra and O₂-TPD. The synthesis of Fe⁴⁺-containing LaFeO₃ perovskite by ball milling was able to produce the O₂ adsorption capacity of nonsubstituted perovskite-type oxide.

DOI： 10.1111/jace.13513

Language：English   Publishing type：Research paper (scientific journal)  

Pd/LaFeO₃/Al₂O₃ catalysts were prepared by co-deposition of Pd and LaFeO₃ perovskite oxides in the intrapores of Al₂O₃ by the incipient wetness method. Pd and LaFeO₃ perovskite oxides were highly dispersed on Al₂O₃ in the inside pore. H₂-TPR studies revealed that the oxidation state, dispersion and redox properties of Pd were affected by the presence of LaFeO₃ with close proximity. The Pd and LaFeO₃ co-deposited Al₂O₃ catalysts exhibited much higher activity for CO oxidation and NO–CO reaction than Pd/Al₂O₃ catalysts.

DOI： 10.1007/s11144-014-0823-y

Language：English   Publishing type：Research paper (scientific journal)  

DOI： 10.1039/c4ta06988a

Language：English   Publishing type：Research paper (scientific journal)  

Ce-based oxides were prepared by citric acid complex method and characterized by nitrogen physisorption, XRD, BET, H₂-TPR and XPS; their catalytic performances in simultaneous removal of diesel soot and NO_x were investigated on a thermogravimetric apparatus and a tubular reactor. Co_0.1/CeLa_0.05 prevailed over all the detected materials in catalytic performance for simultaneous removal of soot and NO_x. T₅₀ of this catalyst (temperature for 50% soot combustion)was 301℃, and the yield of N₂ was 41.4%. A majority of cobalt oxides were dispersed on the surface of Ce-La solid solution. The mutual transformation between Co³⁺ and Co²⁺enhanced the redox ability and oxygen storage capacity of pure ceria oxide, achieving lower temperature of combustion. Cerium-cobalt complex oxide doped with lanthanum presented a tremendous increase of surface area, leading to higher yield of N₂. The formation of trace amount of LaCoO₃ promoted oxygen vacancies creation, thus affecting positively to the soot combustion activity.

Language：English   Publishing type：Research paper (scientific journal)  

Copper-manganese (Cu-Mn) mixed oxide catalysts were prepared by a coprecipitation technique from metal nitrates in aqueous solution using tetramethylammonium hydroxide (TMAH) as a pH regulator. The structures and properties of the mixed oxide catalysts were investigated by X-ray diffraction, extended X-ray absorption fine structure, X-ray photoelectron spectroscopy and H₂-TPR studies. Spinel-type mixed oxides were mainly formed in the Cu-Mn mixed oxides in which Cu and Mn species occupied both tetrahedrally and octahedrally coordinated sites. The occupancy of Cu and Mn in these sites depended on the Cu/Mn ratio. The average oxidation state of Cu was evaluated to be 2+ and was almost independent of the Cu/Mn ratio; reduced Cu species were also formed on the surface sites. By incorporation of Cu into Mn oxides, the average oxidation state of Mn increased both in the bulk sites and on the surface sites. The concentration of Mn on the surface sites was higher than that in the bulk sites. The Cu-Mn mixed catalysts exhibited higher activity than corresponding single-metal oxides at the reaction temperature range of 343-403 K. Formation of Cu-Mn spinel-type oxides gave rise to the increase in the catalyst surface area and the rate for CO oxidation normalized by surface area, and the Cu-Mn mixed oxides with the Cu/Mn molar ratio of 1 exhibited the highest activity for CO oxidation. CO-TPR studies revealed that in the temperature range of 343-403 K, the lattice oxygen at the first layer of the mixed oxides reacted with CO to form CO₂. This journal is

DOI： 10.1039/c4cy00660g

Language：English  

DOI： 10.1016/j.cattod.2012.04.033

Language：English  

DOI： 10.1016/j.cattod.2011.10.030

Language：English  

Language：English   Publishing type：Research paper (scientific journal)  

Novel Bi _0.5M _0.5VO ₄ (BMV; M=La, Eu, Sm and Y) solid solutions were prepared and studied in this paper. All the samples were proved to produce H ₂ and O ₂ simultaneously from pure water under the irradiation of UV light. MO bond lengths were proved to increase with M cations by refining cell parameters and atomic positions. Besides, band gaps, energy gaps and photocatalytic activities of BMV also changed with M cations. Both of MO and VO bond lengths were suggested to account for this phenomenon. Inactive A _0.5Y _0.5VO ₄ (A=La, Ce) for water splitting proved incorporation of Bi rather than distortion of VO ₄ tetrahedron was a critical factor for improving efficiency of overall water splitting by facilitating the generation of electron and hole with lighter effective masses. Replacement of Bi by M cations not only gave indirect effect on band structure but also raised position of conduction band minimum to meet requirement of H ₂ production.

DOI： 10.1016/j.jssc.2011.11.035

Language：English  

DOI： 10.1016/j.snb.2011.08.009

Language：English   Publishing type：Research paper (scientific journal)  

Language：English  

DOI： 10.1016/j.cattod.2011.03.062

Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (other academic)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：Japanese   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Language：English   Publishing type：Research paper (scientific journal)  

Event date： 2010.3

Presentation type：Oral presentation (general)  

Venue：大阪   Country：Japan  

Event date： 2008.11

Presentation type：Oral presentation (general)  

Venue：長崎   Country：Japan  

Event date： 2008.7

Presentation type：Oral presentation (general)  

Venue：ソウル   Country：Korea, Republic of  

Presentation type：Oral presentation (general)  

Venue：神戸市   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：大津   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：熊本   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：札幌   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Event date： 2011.9

Presentation type：Oral presentation (general)  

Venue：甲府   Country：Japan  

Event date： 2010.9

Venue：甲府   Country：Japan  

Event date： 2010.9

Presentation type：Oral presentation (general)  

Venue：甲府   Country：Japan  

Event date： 2010.7

Venue：北九州   Country：Japan  

Event date： 2010.7

Venue：北九州   Country：Japan  

Event date： 2010.5

Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2010.3

Presentation type：Oral presentation (general)  

Venue：大阪   Country：Japan  

Event date： 2009.3

Presentation type：Oral presentation (general)  

Venue：千葉   Country：Japan  

Event date： 2009.3

Presentation type：Oral presentation (general)  

Venue：埼玉   Country：Japan  

Event date： 2008.11

Presentation type：Oral presentation (general)  

Venue：長崎   Country：Japan  

Event date： 2008.9

Presentation type：Oral presentation (general)  

Venue：名古屋   Country：Japan  

Event date： 2008.8

Venue：福岡   Country：Japan  

Event date： 2008.8

Presentation type：Oral presentation (general)  

Venue：福岡   Country：Japan  

Event date： 2008.7

Presentation type：Oral presentation (general)  

Venue：北九州   Country：Japan  

Event date： 2008.7

Presentation type：Oral presentation (general)  

Venue：北九州   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：東京   Country：Japan  

Presentation type：Oral presentation (general)  

Venue：ホノルル、ハワイ   Country：United States  

Presentation type：Oral presentation (general)  

Venue：ホノルル、ハワイ   Country：United States  

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Type：Competition, symposium, etc. 

Number of participants：100