Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Heteroepitaxial integration of β-Ga2O3 on diamond (111) has been achieved using radio frequency magnetron sputtering. The β-Ga2O3 epilayer exhibited a high level of in-plane stacking with {-201} parallel to diamond {111}, as confirmed by X-ray diffraction analyses. Pole figure stereographic projections effectively concluded the inoccupancy of (101) texture in the β-Ga2O3 film. The heterojunction preserved its mechanical integration, crystallinity, and heteroepitaxial characteristics up to 900 °C thermal annealing for 40 min. However, annealing at 1000 °C led to structural degradation, attributed to thermal graphitization at the C–O interface. Notably, post-fabrication thermal annealing at 900 °C significantly reduced the oxygen vacancy density in the β-Ga2O3 epilayer from 24.15 % to 15.07 %.

DOI： 10.1016/j.matlet.2025.138753

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Nanodiamond composite (NDC) films were deposited on biased cemented carbide (WC−6 wt. % Co) substrates using a coaxial arc plasma deposition technique, incorporating sputtered aluminium (Al) interlayers with varying thicknesses (0,50, 100, 300, and 500 nm). This study systematically investigates the durability, friction, and wear behaviour of NDC films, focusing on optimizing Al interlayer thickness to enhance performance in dry and harsh machining conditions. The primary objective was to mitigate interfacial catalytic reactions, particularly Co-induced graphitization, which adversely affect adhesion and mechanical integrity. Experimental findings identified a 100 nm Al interlayer as the optimal configuration, forming a protective Al₂O₃ layer that effectively suppressed graphitization. This resulted in significant improvements in coating performance, including a 79 % increase in adhesion strength, as indicated by a critical load of 17 N for full spallation during scratch testing, and a 62 % enhancement in wear resistance, yielding a wear rate of 7.85 × 10−8 mm³/N.m. Simultaneously, the coefficient of friction (COF) decreased by 71 % compared to the uncoated substrate, maintaining a stable value of 0.09 during dry sliding tests against a rough Al₂O₃ counterpart. The exceptional tribological performance of the optimized NDC coatings is attributed to multiple factors. The refined nanostructure, featuring a dense grain boundary network, facilitated the formation of a lubricating graphitic layer, contributing to low and stable friction. Additionally, the high hardness (75 GPa) and Young's modulus (724 GPa) provided superior wear resistance and load-bearing capacity. These results underscore the potential of Al interlayers to significantly enhance the tribological performance of NDC coatings. However, the improvements in durability remain limited by the low adhesion strength, which remains a critical factor for cutting tools operating under dry machining conditions.

DOI： 10.1016/j.surfin.2025.106367

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

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A novel all‐carbon visible light detector is fabricated on a nitrogen‐doped (N‐doped) single‐crystalline diamond (SCD) with interdigitated nanocarbon ohmic contacts. It has been posited that the formation of nitrogen‐vacancy (NV) centers within the photoabsorption layer serves as an effective strategy to augment the device's detection capabilities. To illustrate the significance of this enhancement, NV density is manipulated and augmented by electron beam irradiation in a moderately N‐doped diamond. Despite the incompetent nitrogen doping, the enhancement of NV density in the diamond active layer has resulted in a substantial enhancement of nearly 1.5 orders of magnitude for several critical detection parameters. The NV‐enabled all‐carbon detector demonstrates a high degree of tolerance toward thermal and corrosive environments. The dark current is maintained at a level below 0.01 pA even when the device is operated at a temperature of 250 °C. The robust interfacial bonding between the diamond and the nanocarbon‐interdigitated electrodes ensures that the device exhibits no physical or performance deterioration when subjected to highly corrosive environments. The results of this study may provide insights that can inform the development of high‐sensitivity, harsh environment immune diamond visible light detectors benefiting from the multiple photon excitation of NV quantum centers.

DOI： 10.1002/smll.202409876

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Sustainable nanodiamond composite (NDC) coatings were deposited on WC − 6%Co substrates using eco-friendly Coaxial Arc Plasma Deposition method at discharge energies of 3.6–9.0 J/pulse. This study optimized discharge energy to enhance adhesion strength, wear resistance, and corrosion resistance, promoting sustainability in preparation and operation of coated cutting tools. NDC coatings, produced without external heating, chemical gases, or cobalt chemical etching, achieved 16 μm thickness with deposition rates ranging from 3.2 to 5.7 μm/h, exhibiting dense and pore-free structures. Hardness peaked at 72.5 GPa at 7.0 J/pulse, slightly decreasing to 65 GPa at 9.0 J/pulse, with Young's modulus showing similar trends. Maximum adhesion strength was 42.5 N achieved at 9.0 J/pulse, attributed to suppressed internal stress at the interface. Wear resistance improved significantly, with wear rates peaking at 1.88E-7 mm3/N·m at 7.0 J/pulse, aligning with hardness and C sp3 content from Raman analysis. The coatings exhibited a low coefficient of friction (0.09), representing a sevenfold reduction compared to uncoated substrates, due to an sp2-rich transfer layer enabling enhanced sliding properties. Corrosion resistance improved in 3.5 wt% NaCl solution, achieving 0.5136 mil/year at 7.0 J/pulse, a 60.4 % improvement, though reduced at 9.0 J/pulse due to presence of larger cauliflower-like particles allowing solution penetration. These results highlight NDC coatings as a sustainable and high-performance alternative coating for WC−6%Co cutting tools.

DOI： 10.1016/j.surfcoat.2025.131844

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

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This study explores the optimization of target-substrate distance (TSD) in coaxial arc plasma deposition technique for depositing nanodiamond composite (NDC) films on unheated WC–Co substrates, with a focus on enhancing properties relevant to cutting tool applications. TSD significantly impacted film growth and adhesion, while hardness and Young’s modulus remained stable within the 10–50 mm TSD range. Increased TSD led to reduced deposition rates and film thickness, but improved quality by eliminating macroparticles and reducing surface roughness. Notably, the NDC film deposited at 10 mm TSD exhibited exceptional adhesion resistance, a thickness of 11.45 μm, low compressive internal stress (2.8 GPa), and a surface roughness (Sa) of 280 nm, coupled with an impressive hardness of 49.12 GPa. This film also achieved a favorable deposition rate of 1.05 nm/s. In comparison, the film deposited at 15 mm TSD displayed a maximum hardness of 51.3 GPa, lower Sa of 179 nm, but a reduced deposition rate of 0.29 nm/s. The estimated C sp³ fraction correlated well with the nanoindentation measurements, while internal stress showed a consistent relationship with film adhesion. These findings suggest that a TSD of 10 mm is optimal for balancing hardness, adhesion, deposition rate, and surface roughness, making NDC films a promising candidate for cutting tool applications.

DOI： 10.1007/s13369-024-09161-9

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Other Link： https://link.springer.com/article/10.1007/s13369-024-09161-9/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Springer Science and Business Media LLC  

The examination on β-FeSi2 thin films prepared via facing-target sputtering onto Si(111), subjected to rapid thermal annealing under varying temperatures of 200–800 °C, revealed numerous changes in the film’s physical traits. The energy-dispersive X-ray spectroscope findings corroborate the anticipated atomic composition, displaying strong Si and small Fe peaks, including C and Al impurities. The Fe/Si proportions barely changed after rapid annealing. Under 200 °C and 400 °C, the X-ray diffractometer spectra indicated that orientation (202/220) and (404/440) of β-FeSi2 were improved by rapid annealing, while surface morphology also revealed gradual enhancement in grain structure and roughness. Temperatures of over 600 °C induced recrystallization of the films, resulting in the reduced orientation peak’s intensities, grain compression, and coarsening. These changes caused the air gap to collapse, turning the film’s surface hydrophilic with contact angles of 86.15° at 600 °C and 63.00° at 800 °C. In contrast, the films retained hydrophobicity with contact angles of 93.40° at 200 °C and 91.20° at 400 °C compared to the as-prepared films of 96.75°. The hardness and Young’s modulus improved with rising temperature to 15.2 GPa and 225.8 GPa at maximum. This has ramifications for their prospective use in self-cleaning and hard-coating applications.

DOI： 10.1007/s10853-024-10539-1

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Other Link： https://link.springer.com/article/10.1007/s10853-024-10539-1/fulltext.html

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Conventional machining lubricants pose environmental hazards and increase production costs. This study addresses this challenge by investigating nanodiamond composite (NDC) coatings deposited on WC–Co substrates as a lubricant-free alternative for sustainable machining. The NDC films show superior hardness (65 GPa) compared to the substrate (22 GPa) and enhanced adhesion (HF2). The NDC's unique self-lubrication results in a low and stable friction coefficient (COF ≤ 0.095) and exceptional wear resistance (7.45 × 10−8 mm3/N·m) in dry tesing against Al2O3 counter-body. Compared to CVD diamond, NDC coatings show a 47.8 % reduction in COF and a 31.65 % enhancement in wear resistance, promoting environmentally friendly machining practices.

DOI： 10.1016/j.ijrmhm.2024.106955

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Cemented carbide (WC−Co) tools suffer from surface abrasion, limiting their performance. This study explores droplet-free tetrahedral amorphous carbon (ta-C) coatings deposited via arc ion plating as a solution. The coatings possess a dense, sp3-rich structure, leading to a remarkable hardness of 60 GPa compared to 37 GPa of WC−Co, and strong adhesion with a critical scratch load of 41 N. Tribological tests confirm their effectiveness. Dry sliding tests show reduced wear and lower CoF (0.123) compared to uncoated tools (0.159). Notably, water-soluble lubricants yielded the best performance (lowest CoF: 0.092, superior wear resistance), while water and mineral oil also improved performance.

DOI： 10.1016/j.matlet.2024.137058

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Language：Japanese   Publishing type：Research paper (international conference proceedings)   Publisher：Interdisciplinary Graduate School of Engineering Sciences, Kyushu University  

Nanodiamond composite (NDC) coatings fabricated by coaxial arc plasma deposition (CAPD) exhibit exceptional structural and mechanical properties, making them promising candidates for advanced cutting tool applications. However, the influence of certain key factors, such as the target-substrate distance (TSD), on the growth and characteristics of NDC films remains unclear. TSD affects the substrate ion current and ion bombardment energy, intimately linked to the structure and tribo-mechanical properties of the protective coatings. Therefore, NDC films were fabricated at diverse TSD values ranging from 5 to 50 mm, and their adhesion, hardness, and modulus of elasticity were investigated. The results revealed that growth and adhesion were significantly affected by TSD, whereas hardness and elastic modulus remained constant (from 10 to 50 mm TSD). The film’s thickness declined from 21.88 to 1.8 μm with increasing TSD, and the film quality improved due to macroparticle elimination. Notably, the sample prepared at a distance of 10 mm exhibited the best adhesion resistance, together with a high thickness of 11.45 μm with a hardness of around 50 GPa. The target-substrate distance was revealed to have a crucial potential for determining the structural and mechanical characteristics of NDC films deposited by CAPD.

DOI： 10.5109/7157981

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Nanodiamond composite (NDC) films, with a notable hardness of 65 GPa and a substantial thickness of 10 µm, were successfully fabricated on unheated WC−Co substrates using cathodic arc plasma deposition (CAPD) technology. Raman and synchrotron-based structural analysis, comparing NDC films with similarly hard tetrahedral amorphous carbon (ta-C) films and chemical vapor deposition (CVD) diamond, unveiled distinctive features. Visible Raman spectroscopy highlighted NDC's unique nanostructured composition, characterized by nanodiamond grains embedded in an amorphous carbon matrix, resulting in a high fraction of C−C sp3 bonds (70 %) and intense σ* C−C resonance contributing to its observed hardness. The small size of diamond crystals induced numerous grain boundaries, as evident through intense t-PA Raman peaks, effectively suppressing internal stress to 2.77 GPa and enabling the deposition of an impressive thickness (10 µm), surpassing the thinness of hard ta-C (< 1 µm). Despite the substantial thickness, NDC films demonstrated remarkable films-substrate adhesion, with no delamination and minimal spallation, in contrast to observed buckling and delamination in CVD diamond during Rockwell testing at various loads (60 Kg and 100 Kg). Additionally, NDC films maintained a stable and low coefficient of friction (≤ 0.1) against an Al2O3 counter-body, compared to the higher coefficient (≥ 0.25) of the bare WC-Co substrate. Furthermore, NDC deposition boasted a rapid rate (3.5 µm/h), significantly exceeding both ta-C and diamond coatings, enhancing its practical applicability. Significantly, the deposition process for NDC films stands out for its environmental friendliness and cost-effectiveness, involving no external heating, chemical reactions, chemical etching of Co, or nanodiamond seeding. The findings underscore the exceptional potential of NDC as a strong competitor to hard ta-C and CVD diamond coatings, especially in advanced cutting tool applications.

DOI： 10.1016/j.mtcomm.2024.109839

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Nanodiamond composite (NDC) films, synthesized using an environmentally friendly PVD coaxial arc plasma deposition technique on commercial cemented carbide (Co 6 wt%) substrates without the need for substrate heating, chemical etching of Co, and chemical gases. These NDC coatings, crafted under specific discharge power conditions (5.2 J/pulse, 120 V, and 1 Hz), with or without a substrate biasing (−100 V, 40 kHz, and 35 % duty cycle), exhibit a distinctive nanostructure characterized by nanodiamond grains embedded in an amorphous carbon (a-C) matrix. Highlighting remarkable mechanical characteristics attributed to highly energetic ejected carbon ion. The coatings boast high hardness (H = 65–82 GPa), Young's modulus (E = 688–780 GPa), plasticity index (H/E = 0.094–0.105), and brittle fracture resistance (H3/E2 = 0.58–0.9 GPa). Additionally, these NDC films manifest a substantial thickness of 7 μm due to low internal stress, along with superior adhesion, anti-wear resistance, and a low friction coefficient (0.1–0.09) through dry sliding against an Al2O3 counterpart. Raman analysis substantiates the nanocomposite structure of the film, underscoring the influential role of biasing in enhancing the characteristics of these environmentally friendly and wear-resistant NDC coatings. Nevertheless, the application of a negative bias led to increased internal stress levels (1.28 to 4.53 GPa), adversely impacting the adhesion between the film and substrate, resulting in a decrease from HF3 to HF6 as per Rockwell C indentation. NDC coatings hold significant potential for extending the lifespan of cutting tools and improving overall machining performance.

DOI： 10.1016/j.surfcoat.2024.130517

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

Silicon-doped nanodiamond composite (Si-NDC) films hold significant promise for advancing cutting tool performance in demanding applications. These films, created through coaxial arc plasma deposition from 1 at.% silicon blended graphite targets, eliminate the need for external heating, chemical reactions, Co etching, or nanodiamond seeding on cemented carbide substrates. This study explores the influence of biasing voltages (0 V, −50 V, and − 100 V) during Si-NDC film deposition on their mechanical properties. As biasing voltage increased from 0 to −100 V, Si-NDC films displayed remarkable improvements in hardness (from 56 to 65 GPa) and Young's modulus (from 535 to 655 GPa). These enhancements stem from the presence of nanodiamonds, C − Si sp3 bonds, and unique features within the amorphous carbon matrix. Nevertheless, this transformation introduced higher internal stress levels (0.88 to 3.75 GPa), adversely affecting film-substrate adhesion, which decreased from a critical load of 31 N to 16.6 N for unbiased and − 100 V biased films, respectively. Intriguingly, unbiased films exhibited enhanced adhesion attributed to the formation of intermetallic compounds like CoSi2 and SiC. Surface roughness increased from 90 nm to 180 nm with −100 V biasing, attributed to droplet attraction. Biasing improved film hardness but aggravated internal stress, impacting adhesion and surface roughness.

DOI： 10.1016/j.ijrmhm.2023.106518

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Trans Tech Publications, Ltd.  

Harvesting large quantities of bananas produces tons of banana peel waste, which causes serious environmental problems in Egypt. Therefore, this study presented the transformation of banana peel waste into nanoactivated carbon for use as a nanoadditive in developing jojoba oil-based bio-grease. To extract nanoactivated carbon, banana peel waste (BP) was thermochemically treated by carbonization, activation, and combined activation/carbonization. The prepared samples were characterized using SEM and XRD. Particle sizes, as calculated by the XRD data for BP, Carbonized banana peels (CBP), carbonized/activated banana peels (CABP), and activated/carbonized (ACBP) were 113.24 nm, 96.56 nm, 86.18 nm, and 93.60 nm respectively. CABP of 0, 0.5, and 1.5 wt.% was mixed with jojoba oil and lithium stearate thickener to prepare the grease. Grease samples were tested for copper corrosion and dropping points. The lowest corrosiveness (1a) and highest dropping point (109 °C) were observed for grease, which had the highest weight of CABP (1.5 wt.%). It was evident that the addition of CABP to the prepared bio-greases had a positive impact on the grease properties.

DOI： 10.4028/p-1vGBQt

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Language：Japanese   Publishing type：Research paper (scientific journal)   Publisher：Elsevier BV  

The current research demonstrates the modification of the wetting behavior and mechanical features as well as structure and morphology of Fe3Si films created via facing target sputtering by the rapid thermal annealing (RTA) with the set RTA temperatures (TRTA) of 200, 400, 600, and 800 °C. Following the RTA process, the crystallinity of Fe3Si developed under 400 °C or below. At the 600 °C and 800 °C TRTA, new crystal orientations emerged for FeSi and then β-FeSi2, respectively. Together with composition results, the Fe3Si films were proven to change into FeSi and then FeSi2 under a high TRTA regime. At temperatures of 600 °C and 800 °C, large crystallites, including the scraggly interface, were observed. The root-mean-square roughness roughened slightly according to the RTA process at TRTA of 600 °C or above. The hydrophobic properties of the Fe3Si film surfaces became hydrophilic after the RTA procedure at a TRTA value above 400 °C. The hardness value of the Fe3Si films evidently increased through RTA at 600 °C and 800 °C. Thus, above 400 °C, the RTA process significantly alters the physical features of as-created Fe3Si films.

DOI： 10.1016/j.heliyon.2023.e22511

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Language：English   Publisher：IOP Publishing  

In this work, we demonstrate the first achievement in heteroepitaxial growth of β-Ga_2O_3 thin films on single crystalline diamond (111) wafers using RF magnetron sputtering. A single monoclinic (β-phase) structure with a monofamily {2^^-01} plane was obtained. XRD pole figure shows (2^^-02) and (002) textures of the (2^^-01) β-Ga_2O_3 plane parallel to (111) diamond with six distinct rotational domains, confirming successful epitaxial growth. Collectively, this research provides valuable insights into the epitaxial growth of β-Ga_2O_3 on diamond via sputtering, paving the way for scalable β-Ga_2O_3/diamond heterostructures for future electronic and optoelectronic applications with not only high performance but also effective self-thermal management.

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

Abstract

<p></p> This study converted slag from the steelmaking industry into an Fe2O3-rich nanocomposite using solvothermal technique for photodegradation of pharmaceutical wastewater in an immobilized mode. The nanocomposite was characterized using XRF, SEM, EDX, TEM, FTIR, XRD, and UV–Vis spectrometer. The XRF analysis result reveals a significant increase in the weight percent of Fe2O3 and SiO2, with a decrease in CaO content. The SEM images revealed the spherical and heterogeneous nature of the nanocomposite in shape and structure, while the FTIR confirms the increase in the vibration band of Si–O–Si and Fe–O with a reduction in the wide stretch mode of Ca–O. The XRD result illustrated the crystalline peak of Fe2O3 with a nanoparticle crystal size of 15.17 nm. The slag nanocomposite was used for the photodegradation of paracetamol. The optimum operating parameters were obtained using response surface methodology at an R2 value of 0.99 and p-value &amp;lt; 0.05. The degradation efficiency obtained at the optimum value was 96.96%. The degradation efficiency of the fifth repeated cycle of the immobilized nanocomposite was 77.89%. The degradation mechanism revealed that OH• radical was the major species of the degradation process. This work showed that slag nanocomposite might be effectively used for pharmaceutical wastewater treatment.

DOI： 10.2166/wpt.2023.152

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

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In this work, we demonstrates the first achievement in heteroepitaxial growth of β-Ga₂O₃ thin films on singlecrystalline diamond (111) wafers using RF magnetron sputtering. A single monoclinic (β-phase) structure with a monofamily {-201} plane was obtained. XRD pole-figure shows (-202) and (002) textures of the (-201) β-Ga₂O₃ plane parallel to (111) diamond with six distinct rotational domains, confirming successful epitaxial growth. Collectively, this research provides valuable insights into the epitaxial growth of β-Ga₂O₃ on diamond via sputtering, paving the way for scalable β-Ga₂O₃/diamond heterostructures for future electronic and optoelectronic applications with not only high-performance but also effective self-thermal management

DOI： 10.35848/1882-0786/acfd07

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Other Link： https://iopscience.iop.org/article/10.35848/1882-0786/acfd07/pdf

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

Abstract

This work describes the polyaniline (PANI) nanoparticles' impregnation into the polystyrene (PS) membrane and its impact on the different membrane properties for the first time. PANI nanoparticles were synthesized separately using the oxidative polymerization technique and then impregnated into the polystyrene‐DMF matrix solution. Membranes were cast via the Non‐Solvent Induced Phase Separation (NIPS) process. The surface and structural properties of the fabricated membranes were thoroughly characterized using contact angle measurement (CA), x‐ray diffraction (XRD), Fourier‐transform infrared spectrometer (FTIR), and scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) and the mechanical characteristics of the membrane were also investigated. According to the CA results, the addition of PANI in the matrix improved the polystyrene membrane's hydrophilicity from 65° to 54.5°. The FTIR spectra revealed that the PANI nanoparticles were successfully impregnated into the PS matrix. SEM images illustrated that the porosity of the PANI‐modified membrane was enhanced by 50% compared to the pristine PS membrane. Furthermore, adding PANI to the PS membrane significantly reduced the average pore size. The filtration experiment showed that PANI modified membrane had 81% rejection of MO dye as compared to the pristine PS membrane which had 60%. Therefore, The PANI added to the PS membrane greatly enhanced the PS membrane's structural properties.

DOI： 10.1002/app.54477

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Language：English   Publishing type：Research paper (scientific journal)   Publisher：Applied Physics Express  

We report on negative bias-enhanced growth of quenched-produced diamond films on titanium using hybrid coaxial arc plasma deposition at room temperature. Optimizing the bias voltage to −40 V resulted in a spontaneous formation of a titanium carbide interfacial layer, which caused a significant increase in the adhesion strength from 16 to 48 N. Selective etching of undesired sp 2-C bonded atoms and ultrafast quenching of the energetic carbon ions (C+) promoted the growth of dense sp 3-C bonded atoms, achieving a superhardness of 96 GPa, comparable to natural diamond. These pioneering findings have the potential to revolutionize multifunctional materials for biomedical applications.

DOI： 10.35848/1882-0786/acdfb7

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

In this study, we report on the novel growth of nanodiamond composite (NDC) films on titanium (Ti) substrates using the coaxial arc plasma deposition (CAPD) at room temperature, which offers several advantages over conventional growth techniques. CAPD employs a unique coaxial arc plasma gun structure that provides a supersaturated condition of highly energetic carbon ions (C^+) for ultrafast quenching on the substrate, promoting the growth of nanodiamond grains. This allows for NDC films' growth on diverse substrates without the need for initial seeding or substrate heating. However, the growth of NDC films on Ti substrates at room temperature is challenging due to the native oxide layer (TiO_2). Here, we grew NDC films on Ti substrates using three different pretreatments: (i) hydrofluoric acid (HF) etching, (ii) insertion of a titanium carbide (TiC) intermediate layer, and (iii) in situ Ar^+ plasma etching. The morphology and structure of the grown NDC films were examined by 3D laser, high-resolution scanning electron microscopies (HR-SEM), Raman, and x-ray photoelectron (XPS) spectroscopies. Our results demonstrate that in situ Ar^+ plasma etching is the most effective pretreatment method for completely removing the native TiO_2 layer compared to the other two ex situ pretreatments, in which re-oxidation is more likely to occur after these pretreatments. Furthermore, NDC films grown using the hybrid Ar^+ ion etching gun (IG) and CAPD exhibit the highest sp^3 content (63%) and adhesion strength (16 N).

DOI： 10.1088/2053-1591/acd992

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

DOI： https://doi.org/10.1016/j.enmm.2023.100836

Language：English   Publishing type：Research paper (scientific journal)   Publisher：Environmental Nanotechnology, Monitoring and Management  

Electrical Furnace Steel slag (EAF) was converted into steel slag nanocomposite (SSNC) by solvothermal preparation technique and assisted by H2O2 for Fenton and photo-Fenton-like degradation of six different dyes in both suspension and spin-coated modes. The physico-chemical properties were evaluated using various characterization tools. The result reveals that the EAF-SSNC exhibited nanocomposite behaviour. As a substrate for studying the advance oxidataion processes, methylene blue (MB) was first used. The kinetic study followed the pseudo-first-order reaction kinetics. The effect of operating factors was studied using the response surface methodology. Based on the optimum parameters, five reusability test was performed for both suspension and spin-coated mode, where 92.89% of MB was degraded in the fifth cycle for suspension mode and 88.21% for spin-coated mode. The photodegradation efficiency of methylene blue, methyl red, rhodamine-B, Congo red, acid blue-25, and methyl orange were 85.84%, 74.62%, 70.53%, 58.66%, 45.21%, and 40.38%, respectively, at a neutral pH. The effect of scavenger and total organic carbon (TOC) were analyzed. Moreover, the degradation pathway was identified using an LC-mass spectrometer. This work showed that slag nanocomposite is effective for dye degradation and lowering the overall cost of the Fenton process at a neutral pH.

DOI： 10.1016/j.enmm.2023.100836

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

The realization of diamond-based advanced devices is interrelated with the fabrication of practical ohmic contacts. Contrary to boron-doped, the phosphorus-doped diamonds with interface carbide forming Ti-based conventional ohmic contacts find their limitation in device fabrication due to the high contact resistance. Herein, nanocarbon ohmic contacts are deposited by a coaxial arc plasma gun on semiconducting diamonds, and their composite structure which facilitates exceptional contact properties is explored. A comparative electrical characterization between nanocarbon ohmic contacts and conventional Ti-based contacts is performed on a heavily phosphorus-doped diamond, and they exhibited one-order declination in specific contact resistance. In addition to the low contact resistance, an ideal ohmic electrode is preferable to have good mechanical adhesion and corrosion resistance for device applications. The contact behavior of n-type diamond/nanocarbon against an extremely corrosive environment realized by boiling H2SO4 + HNO3 solution is analyzed. The nanocarbon ohmic contacts exhibit excellent corrosion resistance and mechanical adhesion over conventional Ti-based contacts. A similar trend is also observed for nanocarbon contacts on boron-doped diamonds. The modest effect on the transfer length of the nanocarbon contacts with respect to acid treatment sessions indicates a tightly bonded diamond/nanocarbon interface and actively suggests their application in highly-corrosive and harsh environments.

DOI： 10.1002/pssa.202200627

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Other Link： https://onlinelibrary.wiley.com/doi/full-xml/10.1002/pssa.202200627

Publisher：Applied Physics Express  

It has been extremely difficult for nanodiamond composite (NDC) films to be deposited on Ti due to a large thermal expansion coefficient difference. The native oxide layer on Ti is another problem preventing the appropriate adhesion of NDC films and subsequent delamination. In this work, innovative room temperature adhesion of 3 μm NDC films with 54 GPa hardness on Ti substrates was accomplished via a hybrid system of ion etching gun and coaxial arc plasma deposition (CAPD). Ar+ plasma etching is capable to terminate the superficial TiO2 layer and manipulates substrate morphology during CAPD provides instantaneous deposition of NDC films at room temperature.

DOI： 10.35848/1882-0786/ac99b6

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DOI： 10.1016/j.jphotochem.2021.113543

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

Effects of Air Exposure on Hard and Soft X-ray Photoemission Spectra of Ultrananocrystalline Diamond/Amorphous Carbon Composite Films
© 2019 by the authors. Hard X-ray photoemission spectroscopy (HAXPES) was employed for the structural evaluation of ultrananocrystalline diamond/amorphous carbon (UNCD/a-C) composite films deposited on cemented carbide substrates, at substrate temperatures up to 550 °C by coaxial arc plasma deposition. The results were compared with those of soft X-ray photoemission spectroscopy (SXPES). Since nanocrystalline diamond grains are easily destroyed by argon ion bombardment, the structural evaluation of UNCD/a-C films, without the argon ion bombardment, is preferable for precise evaluation. For samples that were preserved in a vacuum box after film preparation, the sp3 fraction estimated from HAXPES is in good agreement with that of SXPES. The substrate temperature dependencies also exhibited good correspondence with that of hardness and Young's modulus of the films. On the other hand, the sp3 fraction estimated from SXPES for samples that were not preserved in the vacuum box had an apparent deviation from those of HAXPES. Since it is possible for HAXPES to precisely estimate the sp3 fraction without the ion bombardment treatment, HAXPES is a feasible method for UNCD/a-C films, comprising nanocrystalline diamond grains.

DOI： 10.3390/coatings8100359

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

DOI： https://doi.org/10.1149/07550.0057ecst

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

Nitrogen-Incorporated Amorphous Carbon Catalysts with Higher Reactivity toward Oxygen Reduction Reaction Materials for Alkaline Fuel Cells and Direct Fuel Cells

DOI： 10.1149/07514.1021ecst

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DOI： https://doi.org/10.1149/07513.0153ecst

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

DOI： https://doi.org/10.1149/07513.0139ecst

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

DOI： https://doi.org/10.1149/07516.0217ecst

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

Si and Cr Doping Effects on Growth and Mechanical Properties of Ultrananocrystalline Diamond/Amorphous Carbon Composite Films Deposited on Cemented Carbide Substrates by Coaxial Arc Plasma Deposition

DOI： 10.5109/1657738

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

Fabrication of Ultrananocrystalline Diamond/Nonhydrogenated Amorphous Carbon Composite Films for Hard Coating by Coaxial Arc Plasma Deposition

DOI： 10.5109/1657379

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

DOPING EFFECTS ON ULTRANANOCRYSTALLINE DIAMOND/AMORPHOUS CARBON COMPOSITE FILMS DEPOSITED ON CEMENTED CARBIDE SUBSTRATE BY COAXIAL ARC PLASMA DEPOSITION

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

Ultrananocrystalline Diamond/amorphous Carbon Composite Films Synthesis on Cemented Carbide Substrate by Coaxial Arc Plasma Deposition

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

DOI： https://doi.org/10.1149/2.0261410jes

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

DOI： http://dx.doi.org/10.1088/1742-6596/441/1/012042

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

DOI： http://dx.doi.org/10.1088/1742-6596/441/1/012040

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

DOI： http://dx.doi.org/10.1149/2.007306eel

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

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

DOI： https://doi.org/10.1155/2012/369130

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

DOI： 10.1016/j.diamond.2011.06.017

Event date： 2025.5

Language：English  

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Event date： 2025.5

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2025.3

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2024.12

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2024.12

Presentation type：Oral presentation (general)  

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Event date： 2024.12

Presentation type：Oral presentation (general)  

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Event date： 2024.12

Presentation type：Oral presentation (general)  

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Event date： 2024.12

Presentation type：Oral presentation (general)  

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Event date： 2024.12

Presentation type：Oral presentation (general)  

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Event date： 2024.11

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Event date： 2024.11

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Event date： 2024.11

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2024.6

Presentation type：Poster presentation  

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Event date： 2024.6

Language：Japanese   Presentation type：Public lecture, seminar, tutorial, course, or other speech  

Country：Japan  

Event date： 2024.1 - 2024.2

Language：Japanese  

Country：Japan  

Event date： 2024.1

Language：Japanese  

Venue：九州大学馬出キャンパス 九州大学医学部百年講堂，福岡県福岡市東区   Country：Japan  

Event date： 2023.12

Language：Japanese  

Venue：九州工業大学飯塚キャンパス，福岡県飯塚市   Country：Japan  

Event date： 2023.11

Language：English  

Country：Japan  

Event date： 2023.11

Language：English   Presentation type：Oral presentation (general)  

Venue：Ito Campus, Kyushu University, Fukuoka, Japan   Country：Japan  

Event date： 2023.11

Language：English  

Country：Japan  

Event date： 2023.11

Language：English  

Country：Japan  

Event date： 2023.11

Language：English   Presentation type：Oral presentation (invited, special)  

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Event date： 2023.11

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2023.11

Language：Japanese  

Country：Japan  

Event date： 2023.11

Language：English  

Country：Taiwan, Province of China  

Event date： 2023.11

Language：English  

Country：Taiwan, Province of China  

Event date： 2023.10

Language：English  

Country：Japan  

Event date： 2023.10

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2023.9

Language：Japanese  

Venue：熊本城ホール，熊本県熊本市中央区   Country：Japan  

Event date： 2023.9

Language：English   Presentation type：Oral presentation (general)  

Venue：Palau de Congressos de Palma, Mallorca, Spain   Country：Spain  

Event date： 2023.9

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2023.6

Language：Japanese  

Country：Japan  

Event date： 2023.6

Language：Japanese  

Venue：Ishikawa Industrial Promotion Center, Japan   Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2023.3

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.11

Language：English   Presentation type：Oral presentation (general)  

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Event date： 2022.11

Language：English  

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Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.10

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.9

Language：Japanese   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.7

Language：Japanese  

Country：Japan  

Event date： 2022.7

Language：Japanese  

Country：Japan  

Event date： 2022.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Kanazawa Bunka Hall, Kanazawa, Ishikawa   Country：Japan  

Event date： 2022.6

Language：English   Presentation type：Oral presentation (general)  

Country：Japan  

Event date： 2022.6

Language：English   Presentation type：Oral presentation (general)  

Venue：Kanazawa Bunka Hall, Kanazawa, Ishikawa   Country：Japan  

Event date： 2022.3

Language：Japanese  

Country：Other  

Event date： 2022.3

Language：English  

Country：Other  

Event date： 2021.12

Language：English  

Country：Other  

Event date： 2021.12

Language：English  

Country：Other  

Event date： 2021.12

Language：English  

Country：Other  

Event date： 2021.12

Language：Japanese  

Country：Other  

Event date： 2021.12

Language：Others  

Country：Other  

Nanodiamond composite film coated on Titanium substrates by Arc Plasma Deposition for biomedical applications

Event date： 2021.12

Language：Others  

Country：Other  

Event date： 2021.12

Language：Others  

Country：Other  

Event date： 2021.12

Language：Others  

Country：Other  

PVD nanodiamond composite hard coatings for cutting tools application: structural, mechanical, and tribological properties

Event date： 2021.11

Language：English   Presentation type：Oral presentation (general)  

Country：Taiwan, Province of China  

Event date： 2021.6

Language：English  

Country：Other  

Mechanical and structural properties of Si doped nanodiamond composite coat-ings deposited on cemented carbide

Event date： 2021.3

Language：Others  

Country：Other  

Event date： 2021.3

Language：Others  

Country：Other  

Event date： 2020.3

Language：Japanese  

Country：Other  

Event date： 2020.3

Language：Japanese  

Country：Other  

Event date： 2020.3

Language：Japanese  

Country：Other  

Event date： 2020.3

Language：Japanese  

Country：Other  

Event date： 2020.3

Language：Japanese  

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Event date： 2020.3

Language：Others  

Country：Other  

Language：English  

Country：Other  

Development of Heterojunction Solar Cells Comprising Boron-doped Silicon-Carbon Based Semiconductor Thin Films and n-Si

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：Japanese  

Venue：神奈川大学横浜キャンパス   Country：Other  

Language：Japanese  

Venue：神奈川大学横浜キャンパス   Country：Other  

Language：English  

Venue：Boston, Massachusetts, USA   Country：Other  

Language：Japanese  

Venue：徳島大学常三島キャンパス   Country：Other  

Language：Japanese  

Venue：徳島大学常三島キャンパス   Country：Other  

Language：Japanese  

Venue：慶應義塾大学日吉キャンパス・矢上キャンパス   Country：Other  

Language：Japanese  

Venue：慶應義塾大学日吉キャンパス・矢上キャンパス   Country：Other  

Language：Japanese  

Venue：慶應義塾大学日吉キャンパス・矢上キャンパス   Country：Other  

Language：English  

Venue：Prague, Czech Republic   Country：Other  

Language：English  

Venue：Kyoto University, Kyoto, Japan   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：English  

Venue：Kyoto University, Kyoto, Japan   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：English  

Venue：Kyoto University, Kyoto, Japan   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：English  

Venue：Kyoto University, Kyoto, Japan   Country：Other  

Language：English  

Venue：Hawaii Convention Center, Honolulu, Hawaii, USA   Country：Other  

Language：Japanese  

Venue：立命館大学びわこ・くさつキャンパス   Country：Other  

Language：Japanese  

Venue：立命館大学びわこ・くさつキャンパス   Country：Other  

Language：English  

Venue：Strasbourg, France   Country：Other  

Language：English  

Venue：Strasbourg, France   Country：Other  

Language：Japanese  

Venue：サンメッセ鳥栖，佐賀県鳥栖市   Country：Other  

Language：Japanese  

Venue：サンメッセ鳥栖，佐賀県鳥栖市   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：English  

Venue：Chikushi campus, Kyushu University, Kasugakouen, Kasuga, Fukuoka, Japan.   Country：Other  

Language：Japanese  

Venue：広島国際会議場   Country：Other  

Language：Japanese  

Venue：北九州国際会議場   Country：Other  

Language：Japanese  

Venue：北九州国際会議場   Country：Other  

Language：Japanese  

Venue：佐賀県立九州シンクロトロン光研究センター   Country：Other  

Language：English  

Venue：Fukuoka University, fukuoka, Fukuoka, Japan   Country：Other  

Language：English  

Venue：Fukuoka University, fukuoka, Fukuoka, Japan   Country：Other  

Language：English  

Venue：Fukuoka University, Fukuoka, Fukuoka, Japan   Country：Other  

Language：Japanese  

Venue：佐賀県立九州シンクロトロン光研究センター   Country：Other  

Language：Japanese  

Venue：北海道大学札幌キャンパス   Country：Other  

Language：English  

Venue：Kunibiki Messe, Matsue, Shimane, Japan   Country：Other  

Language：English  

Venue：Kunibiki Messe, Matsue, Shimane, Japan   Country：Other  

Language：English  

Venue：Chikushi campus, Kyushu University, Kasugakouen, Kasuga, Fukuoka, Japan.   Country：Other  

Language：Japanese  

Venue：大分大学旦野原キャンパス   Country：Other  

Language：English  

Venue：Hapuna Beach Prince Hotel, Kohala Coast, Hawaii, USA   Country：Other  

Language：English  

Venue：Hapuna Beach Prince Hotel, Kohala Coast, Hawaii, USA   Country：Other  

Language：English  

Venue：大分大学旦野原キャンパス   Country：Other  

Language：Japanese  

Venue：立命館大学びわこ・くさつキャンパス   Country：Other  

Language：Japanese  

Venue：立命館大学びわこ・くさつキャンパス   Country：Other  

Language：Japanese  

Venue：北九州国際会議場   Country：Other  

Language：English  

Venue：C-Suite hotel , Nimes ,France   Country：Other  

Language：Japanese  

Venue：名古屋国際会議場   Country：Other  

Language：English  

Venue：Chikushi campus, Kyushu University, Kasuga, Fukuoka, Japan.   Country：Other  

Language：English  

Venue：Chikushi campus, Kyushu University, Kasuga, Fukuoka, Japan.   Country：Other  

Language：Japanese  

Venue：東京大学柏の葉キャンパス   Country：Other  

Language：Japanese  

Venue：東京大学柏の葉キャンパス   Country：Other  

Language：English  

Venue：Nishijin Plaza   Country：Other  

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Venue：朱鷲メッセ   Country：Other  

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Venue：Honolulu, Hawaii   Country：Other  

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Venue：Honolulu, Hawaii   Country：Other  

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Venue：Honolulu, Hawaii   Country：Other  

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Venue：Honolulu, Hawaii   Country：Other  

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Venue：The University of Tokyo, Tokyo   Country：Other  

Language：English  

Venue：Honolulu, Hawaii   Country：Other  

Language：English  

Venue：Honolulu, Hawaii   Country：Other  

Language：English  

Venue：対馬市交流センター，長崎県対馬市   Country：Other  

Language：English  

Venue：神戸芸術センター，兵庫県神戸市   Country：Other  

Language：Japanese  

Venue：パシフィコ横浜，神奈川県横浜市   Country：Other  

Language：Japanese  

Venue：パシフィコ横浜，神奈川県横浜市   Country：Other  

Language：Japanese  

Venue：パシフィコ横浜，神奈川県横浜市   Country：Other  

Language：Japanese  

Venue：慶應義塾大学日吉キャンパス，神奈川県横浜市   Country：Other  

Language：Japanese  

Venue：慶應義塾大学日吉キャンパス，神奈川県横浜市   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

Language：Japanese  

Venue：長崎大学文教キャンパス   Country：Other  

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Nitrogen-doped amorphous carbon catalysts having higher reactivity toward oxygen reduction reaction by controlling surface quinone and carboxy groups

Language：Japanese  

Country：Other  

Language：Japanese  

Country：Other  

Language：Japanese  

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Language：Japanese  

Country：Other  

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