|Jin Miyawaki||Last modified date：2018.08.31|
Associate Professor / Department of Advanced Device Materials
Institute for Materials Chemistry and Engineering
Institute for Materials Chemistry and Engineering
Homepage of Yoon and Miyawaki laboratory .
Doctor of Science
Field of Specialization
My research subject is development of new high-efficiency functional carbonaceous materials to solve energy and environmental problems. I guide students and researchers through daily research and educate them through seminars. Our laboratory accepts many foreign researchers.
Research InterestsMembership in Academic Society
- Development of carbon material for adsorption heat pump
keyword : Carbon material, Adsorption heat pump, Adsorption amount, Adsorption kinetics
- Elucidation of surface and pore properties of carbon materials by solid-state NMR method using water molecule as a surface probe
keyword : adsorption, surface, pore, carbon materials, water molecule, surface probe, solid-state NMR
- Mechanism elucidation of development of pore structure by using hyper-polarized 129Xe-NMR technique
keyword : adsorption, pore, carbon materials, hyper-polarized 129Xe-NMR
- Development of carbon materials having shallow hydrophobic pores as high performance adsorbent even in humid atmosphere
keyword : adsorption, competive adsorption, pore, carbon materials
2008.02～2010.03Most of porous materials lose their adsorption ability under high humid condition because of inhibitive adsorption of water molecules. To overcome this problem, I introduce new concept to new carbonaceous porous material. The carbon material, which I will try to prepare, possesses shallow hydrophobic pores. The hydrophobicity and shallowness of pores and would allow easy desorption of water molecules..
- Influence of various factors, such as pore size, surface functional groups, and surface structure, on 129Xe NMR spectra was quantitatively elucidated. The findings would enable to investigate pore structure and its development mechanism of carbonaceous porous materials, which have been difficult only by nitrogen adsorption measurements at 77 K.
- Pitch based carbon fiber for the application of CFRP will be developed using POSCO coal tar as a raw material. The target properties of developed carbon fiber are as follow; Tensile strength: over 150 kg/mm2, Elongation: over 1.5 %, Compressive strength: over 70% of TS.
- This project aims to develop high efficiency catalysts, with which gasification process progresses at low reaction temperature, and to fabricate the gasification process, in which enables catalyst separation.
- Elucidation of reaction mechanism of O2/CO2 coal gasification and its application to various coals in Asia
- Development of prompt and continuous technologies for air quality conservation using activated carbon fibers and activated carbon nano-fibers
- Low temperature operational fuel cells such as direct methanol (DMFC) and polymer electrolyte membrane fuel cells (PEMFC) come into spotlight as promising power sources for many applications such as small portable electric devices, automotive and stationary domestic applications. Although a number of researches have been performed for last two decades, further development is still very necessary to reduce the cost markedly by decreasing the used amount of noble metals in the catalyst through the improvement of catalytic activities. In this study, the structure-controlled carbon nanofibers (CNFs) were synthesized to develop improved catalyst supports both for anode and cathode. The performances of the catalysts prepared by the selected CNFs were examined in both electrodes of DMFC and PEMFC.
Very thin (diameter of 7 to 20 nm, denoted as CM55 for DMFC anode) and thin (40 to 70nm, NFM415 for PEMFC anode) Herringbone-type CNFs were attempted to be highly dispersed using a nano-dispersion equipment (T.K. FILMICSR Model 56-50, Primix Co., Japan) for releasing entangled network with specially designed impeller agitation of 16500 rpm for 30 minutes in distilled water. The maximum power densities of a commercial catalyst, Johnson Matthey PtRu60wt% catalyst (Pt: 2, Ru: 1, and Carbon: 2 mg/cm2), was 55, 121, 162 mW/cm2 at 30, 60, 90℃, respectively, for the DMFC anode. In comparison, the single cell performances of PtRu40wt% anode catalyst supported on CM55 for DMFC (Pt: 1.33, Ru: 0.67, and Carbon: 3 mg/cm2) were 62, 156 and 224 mW/cm2 at the cell temperature of 30, 60, and 90oC, respectively, even if the Pt and Ru contents were reduced by 36%. The high dispersed NFM415 was examined as the anode catalyst support of PEMFC. The Maximum power density of commercial Johnson Matthey catalyst (Pt: 0.45, Carbon: 1.68 mg/cm2) appeared to be 800 mW/cm2 at cell temperature of 80℃. On the other hand, the catalyst prepared by highly dispersed NFM415 and chemical reduction method using NaBH4 showed slightly lower value to be 771 mW/cm2, and the highest performance was observed at the catalyst prepared by NFM415 and reflux method to be 947 mW/cm2 at the same Pt weight base.
GP-CNF-NA as the cathode catalyst support was prepared from Platelet-type CNFs through the graphitization at 2800℃ and nitric acid treatment to improve the oxidative stability for the DMFC and PEMFC cathode catalysts. The commercial Johnson Matthey Pt black (Pt: 2, Carbon: 0 mg/cm2) as the cathode catalyst of DMFC showed the single cell power densities of 46, 116, 164 mW/cm2 at the cell temperature of 30, 60, 90℃, respectively. The DMFC cathode catalyst supported on GP-CNF-NA (Pt: 0.8, Carbon: 1.2 mg/cm2) using chemical reduction method showed slightly lower power densities to be 32, 94, 146 mW/cm2. The Johnson Matthey Pt black (Pt: 3, Carbon: 0 mg/cm2) as the cathode catalyst of PEMFC showed the single cell power densities of 800 mW/cm2 at the cell temperature of 80℃. In comparison, the cathode catalysts using GP-CNF-NA (Pt: 0.4, Carbon: 0.6 mg/cm2) prepared by chemical reduction and reflux method showed the power densities to be 600 and 670 mW/cm2, respectively.
- Development of surface optimized carbon nano-fibers (CNFs) as new environmental catalyst
|1.||Jin Miyawaki, Yao Yu, Doo-Won Kim, Koji Nakabayashi, Seong-Ho Yoon, Development of functional activated carbons, The 1st International Forum on Graphene in Ulanqab & the 16th China-Japan-Korea International Symposium on Carbon Saves the Earth (CSE2018), 2018.08.|
|2.||Jin Miyawaki, KIL HYUNSIG, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 中林 康治, 持田 勲, 尹 聖昊, Development of High-performance Activated Carbon for Adsorption Heat Pump, The 15th Korea-China-Japan Joint Symposium on Carbon Saves the Earth (CSE2017), 2017.09.|
|3.||Hyeonseok Yi, Hiroki Shimanoe, Doowon Kim, Yao Yu, 中林 康治, 尹 聖昊, Jin Miyawaki, PREPARATION OF ACTIVATED CARBON BY PRESSURIZED PHYSICAL ACTIVATION, The World Conference on Carbon 2017: Carbon for Grand Challenges (Carbon2017), 2017.07, [URL].|
|4.||Jin Miyawaki, Doo-Won Kim, KIL HYUNSIG, 中林 康治, 尹 聖昊, Structural elucidation of physical and chemical activation mechanisms of activated carbons based on the microdomain structure model, 6th Symposium on Challenges for Carbon-based Nanoporous Materials, 2017.07, [URL].|
|5.||Jin Miyawaki, KIL HYUNSIG, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 中林 康治, 持田 勲, 尹 聖昊, Development of High-performance Activated Carbons for Adsorption Heat Pump
, The 5th Symposium on Challenges for Carbon-based Nanoporous Materials (5th CBNM2016-NAGANO), 2017.02.
|6.||Jin Miyawaki, KIL HYUNSIG, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 中林 康治, 持田 勲, 尹 聖昊, Development of Innovative Activated Carbons for Adsorption Heat Pump Application, 第４３回炭素材料学会年会, 2016.12.|
|7.||KIL HYUNSIG, 中林 康治, 尹 聖昊, Jin Miyawaki, Porosity Improvement of Activated Carbon by Multiple Chemical Activation, 第４３回炭素材料学会年会, 2016.12.|
|9.||KIL HYUNSIG, Koichiro Hata, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 持田 勲, 中林 康治, 尹 聖昊, Jin Miyawaki, Development of Activated Carbons for Adsorption Heat Pumps, 2016 AIChE Annual Meeting, 2016.11, [URL].|
|10.||Hyun-Sig Kil, Animesh Pal, Bidyut Baran Saha, 持田 勲, 中林 康治, 尹 聖昊, Jin Miyawaki, Preparation and ethanol adsorption properties of activated carbons from biomass for adsorption heat pumps
, IVth International Symposium on Innovative Materials for Processes in Energy Systems 2016 (IMPRES 2016), 2016.10, [URL].
|11.||Jin Miyawaki, KIL HYUNSIG, Koichiro Hata, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 持田 勲, 中林 康治, 尹 聖昊, Development of innovative activated carbons for adsorption heat pumps, IVth International Symposium on Innovative Materials for Processes in Energy Systems 2016 (IMPRES 2016), 2016.10, [URL].|
|12.||Doo-Won Kim, Hyun-Sig Kil, 中林 康治, 尹 聖昊, Jin Miyawaki, Elucidation of mechanism of steam and KOH activation processes by the microdomain model, The 14th Japan-China-Korea Joint Symposium on Carbon Saves the Earth (CSE2016) - New “Traditional” Carbon Materials for High-efficiency Energy Utilization and Environmental Protection –, 2016.09.|
|13.||Jin Miyawaki, Quantitative analysis of electrolyte ions in pores of activated carbons using solid-state NMR, 2015 Kyushu-Tsinghua Universities Joint Seminar on Environmental Protection, 2015.03.|
|14.||JOO-IL PARK, Wei Wei Pang, Luyang Yuan, Masashi Yasudome, CUI QINGYAN, 宮脇 仁, 尹 聖昊, 持田 勲, Heavy oil upgrading, JPIJS九州地区討論会 ～石油産業の役割と若手エンジニアの未来像～, 2014.09.|
|15.||宮脇 仁, TAEGON KIM, Masanori Saito, Yusuke Shingai, Koji Saito, Choong Kyun Rhee, 持田 勲, 尹 聖昊, Quantitative analysis of electrolyte ions in EDLC electrode using solid-state NMR, 2nd Spain-Japan Joint Symposium for Advanced Supercapcitors, 2014.09.|
|16.||宮脇 仁, Hyun-Sig Kil, Ryohei Miyamae, Koichiro Hata, Keiko Ideta, Tomonori Ohba, Hirofumi Kanoh, 持田 勲, 尹 聖昊, Improvement of ethanol adsorptivity of activated carbons for adsorption heat pump, Carbon2014, World Conference on Carbon, 2014.07.|
|17.||Hyun Sig Kil,, Koichiro Hata, Keiko Ideta, Isao Mochida, Seongho YOON, Jin Miyawaki, Influence of surface functionality on ethanol adsorption behavior in activated carbons analyzed by solid-state NMR, Innovative Materials for Processes in Energy Systems, 2013.09.|
|18.||Hyun Sig Kil,, Koichiro Hata, Keiko Ideta, Isao Mochida, Seongho YOON, Jin Miyawaki, Influence of surface functionality on ethanol adsorption behavior in activated carbons analyzed by solid-state NMR, Innovative Materials for Processes in Energy Systems, 2013.09.|
|19.||Nor'Azizi Bin Othman, YUN JUMI, Jin Miyawaki, Isao Mochida, Seongho YOON, H2S removal using activated carbon from waste palm tree trunk, The Annual World Conference on Carbon (Carbon 2013), 2013.07.|
|20.||Koichiro Hata, Keiko Ideta, Ryohei Miyamae, Yuzo Ohata, Hyunsig Kil, Shigemi Toda, Ryusuke Harada, Jin Miyawaki, Isao Mochida, Seongho YOON, NMR analysis of water adsorption behavior in carbon micropores, The Annual World Conference on Carbon (Carbon 2013), 2013.07.|
|21.||Koichiro Hata, Yuzo Ohata, Keiko Ideta, Shigemi Toda, Ryusuke Harada, Jin Miyawaki, Isao Mochida, Seongho YOON, Elucidation of surface properties of carbon blacks by solid-state NMR using waer molecule as a surface probe, The Annual World Conference on Carbon (Carbon 2013), 2013.07.|
|23.||Intravenous toxicity of carbon nanohorns, [URL].|
- The Japan Society on Adsorption
- The Carbon Society of Japan
- The Chemical Society of Japan