ハイエントロピー固溶ナノ合金の創製と新機能探索

• Project Area: High Entropy Alloys - Science of New Class of Materials Based on Elemental Multiplicity and Heterogeneity
• Project/Area Number: 19H05170
• Research Category: Grant-in-Aid for Scientific Research on Innovative Areas (Research in a proposed research area)
• Allocation Type: Single-year Grants
• Review Section: Science and Engineering
• Research Institution: Kyoto University
• Principal Investigator: 北川 宏 京都大学, 理学研究科, 教授 (90234244)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Project Status: Discontinued (Fiscal Year 2020)
• Budget Amount: ¥9,490,000 (Direct Cost: ¥7,300,000、Indirect Cost: ¥2,190,000); Fiscal Year 2020: ¥5,200,000 (Direct Cost: ¥4,000,000、Indirect Cost: ¥1,200,000); Fiscal Year 2019: ¥4,290,000 (Direct Cost: ¥3,300,000、Indirect Cost: ¥990,000)
• Keywords: ハイエントロピー / ナノ合金 / 多元素 / 触媒 / 貴金属 / ナノ固溶合金 / 多元素工エントロピー / ナノ材料 / 多元素高エントロピー

Outline of Research at the Start

本研究では、主にバルク状態では相分離する金属元素の組み合わせを多元素高エントロピー効果により原子レベルで固溶化させることで、多くの新しいナノ物質を創製すると共に、革新的なナノ材料の開発を行う。研究代表者は、2010 年に、元素周期律表上でパラジウムの両隣に位置する銀とロジウムを原子レベルで固溶させることに世界で初めて成功し、Ag-Rh 固溶合金がパラジウムと類似の性質を有することを見出した。謂わば「現代の錬金術」とも言える成果であり、「人工パラジウム」「擬パラジウム」として世界中で広く報道された。

Outline of Annual Research Achievements

令和元年度には、化学還元法を用いて、5元、6元系ハイエントロピー合金の合成に成功しており、本年度は8元系貴金属固溶ナノ合金の合成に取り組んだ。また、昨年度、電極触媒として高い活性を示すことが分かった5元系および6元系ハイエントロピーナノ合金における触媒機構をX線光電子分光を始めとした各種分析を行うことで考察した。
液相還元法により貴金属全8元素から構成されるRuRhPdAgOSIrPtAuナノ合金の合成に成功し、これらを任意の金属組成で合成することが可能となった。また、ソルボサーマル連続フロー合成装置を用いて、昨年度バッチ合成で得られていた5元系RuRhPdIrPtナノ合金の合成にも成功した。また、昨年度電極触媒として物性評価を行ったところ、5元系合金は燃料電池の半反応である水素発生反応（HER）において、酸性およびアルカリ性の両条件において高い活性を示し、それはベンチマークであるPt触媒より高活性を示すことが分かっていた。HERは反応基質である水素原子の吸着エネルギーが触媒金属のdバンドの重心と線形的な相関があるため、dバンド重心によりその活性が予想できることが知られている。そこで、放射光を用いた硬X線光電子分光法により、合成したナノ合金および単金属ナノ粒子の価電子帯の直接観察を行い、そのd-バンド重心と触媒活性の比較を行ったところ、酸性およびアルカリ性溶液共に、RuRhPdIrPtナノ合金触媒は単金属のd-バンド重心理論に従わない極めて高い触媒活性を示すことが分かった。これは、これまでd-バンド重心理論が単純な金属表面をモデルとした水素吸着エネルギーから構成されている点が相違を生んでいる可能性や、開発したHEAがこれまでとは異なる反応機構を示している可能性を示唆した。その他の成果として、排ガス浄化触媒用途や水電解触媒に関する論文などを公表した。

Research Progress Status

令和2年度が最終年度であるため、記入しない。

Strategy for Future Research Activity

令和2年度が最終年度であるため、記入しない。

Research Products

• [Journal Article] Highly Stable and Active Solid‐Solution‐Alloy Three‐Way Catalyst by Utilizing Configurational‐Entropy Effect (2021)
  • Author(s): Kusada Kohei, Wu Dongshuang, Nanba Yusuke, Koyama Michihisa, Yamamoto Tomokazu, Tran Xuan Quy, Toriyama Takaaki, Matsumura Syo, Ito Ayano, Sato Katsutoshi, Nagaoka Katsutoshi, Seo Okkyun, Song Chulho, Chen Yanna, Palina Natalia, Kumara Loku Singgappulige Rosantha, Hiroi Satoshi, Sakata Osami, Kitagawa Hiroshi et al.
  • Journal Title: Advanced Materials Volume: in press Issue: 16 Pages: 2005206-2005206
  • DOI: 10.1002/adma.202005206
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Efficient overall water splitting in acid with anisotropic metal nanosheets (2021)
  • Author(s): Wu Dongshuang、Kusada Kohei、Yoshioka Satoru、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Chen Yanna、Seo Okkyun、Kim Jaemyung、Song Chulho、Hiroi Satoshi、Sakata Osami、Ina Toshiaki、Kawaguchi Shogo、Kubota Yoshiki、Kobayashi Hirokazu、Kitagawa Hiroshi
  • Journal Title: Nature Communications Volume: 12 Issue: 1 Pages: 1145-1145
  • DOI: 10.1038/s41467-021-20956-4
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] First synthesis of air-stable NiZn homogeneous alloy nanoparticles through chemical reduction (2021)
  • Author(s): Okamoto Shinya、Kusada Kohei、Hashiba Hiroshi、Yotsuhashi Satoshi、Kitagawa Hiroshi
  • Journal Title: Materials Advances Volume: 2 Issue: 2 Pages: 684-687
  • DOI: 10.1039/d0ma00883d
  • Peer Reviewed
• [Journal Article] Nonequilibrium Flow-Synthesis of Solid-Solution Alloy Nanoparticles: From Immiscible Binary to High-Entropy Alloys (2020)
  • Author(s): Kusada Kohei、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Sato Katsutoshi、Nagaoka Katsutoshi、Terada Kenji、Ikeda Yasuyuki、Hirai Yoshinari、Kitagawa Hiroshi
  • Journal Title: The Journal of Physical Chemistry C Volume: 125 Issue: 1 Pages: 458-463
  • DOI: 10.1021/acs.jpcc.0c08871
  • Peer Reviewed
• [Journal Article] Platinum-Group-Metal High-Entropy-Alloy Nanoparticles (2020)
  • Author(s): Wu Dongshuang、Kusada Kohei、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Kawaguchi Shogo、Kubota Yoshiki、Kitagawa Hiroshi
  • Journal Title: Journal of the American Chemical Society Volume: 142 Issue: 32 Pages: 13833-13838
  • DOI: 10.1021/jacs.0c04807
  • Peer Reviewed
• [Journal Article] Significant Enhancement of Hydrogen Evolution Reaction Activity by Negatively Charged Pt through Light Doping of W (2020)
  • Author(s): Kobayashi Daiya、Kobayashi Hirokazu、Wu Dongshuang、Okazoe Shinya、Kusada Kohei、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Kawaguchi Shogo、Kubota Yoshiki、Aspera Susan Me?ez、Nakanishi Hiroshi、Arai Shigebumi、Kitagawa Hiroshi
  • Journal Title: Journal of the American Chemical Society Volume: 142 Issue: 41 Pages: 17250-17254
  • DOI: 10.1021/jacs.0c07143
  • Peer Reviewed
• [Journal Article] Coreduction methodology for immiscible alloys of CuRu solid-solution nanoparticles with high thermal stability and versatile exhaust purification ability (2020)
  • Author(s): Huang Bo、Kobayashi Hirokazu、Yamamoto Tomokazu、Matsumura Syo、Nishida Yoshihide、Sato Katsutoshi、Nagaoka Katsutoshi、Haneda Masaaki、Kawaguchi Shogo、Kubota Yoshiki、Kitagawa Hiroshi
  • Journal Title: Chemical Science Volume: 11 Issue: 42 Pages: 11413-11418
  • DOI: 10.1039/d0sc03373a
  • Peer Reviewed
• [Journal Article] On the electronic structure and hydrogen evolution reaction activity of platinum group metal-based high-entropy-alloy nanoparticles (2020)
  • Author(s): Wu Dongshuang、Kusada Kohei、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Gueye Ibrahima、Seo Okkyun、Kim Jaemyung、Hiroi Satoshi、Sakata Osami、Kawaguchi Shogo、Kubota Yoshiki、Kitagawa Hiroshi
  • Journal Title: Chemical Science Volume: 11 Issue: 47 Pages: 12731-12736
  • DOI: 10.1039/d0sc02351e
  • Peer Reviewed / Open Access / Int'l Joint Research
• [Journal Article] NMR-based gap behavior related to the quantum size effect (2020)
  • Author(s): Okuno Tomonori、Manago Masahiro、Kitagawa Shunsaku、Ishida Kenji、Kusada Kohei、Kitagawa Hiroshi
  • Journal Title: Physical Review B Volume: 101 Issue: 12 Pages: 121406-121406
  • DOI: 10.1103/physrevb.101.121406
  • Peer Reviewed
• [Journal Article] Synthesis of Mo and Ru solid-solution alloy NPs and their hydrogen evolution reaction activity (2020)
  • Author(s): Okazoe Shinya、Kusada Kohei、Wu Dongshuang、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Kawaguchi Shogo、Kubota Yoshiki、Kitagawa Hiroshi
  • Journal Title: Chemical Communications Volume: 56 Issue: 92 Pages: 14475-14478
  • DOI: 10.1039/d0cc05958g
  • Peer Reviewed
• [Journal Article] Crystalline to amorphous transformation in solid-solution alloy nanoparticles induced by boron doping (2020)
  • Author(s): Kobayashi Keigo、Kusada Kohei、Wu Dongshuang、Ogiwara Naoki、Kobayashi Hirokazu、Haruta Mitsutaka、Kurata Hiroki、Hiroi Satoshi、Seo Okkyun、Song Chulho、Chen Yanna、Kim Jaemyung、Tayal Akhil、Sakata Osami、Ohara Koji、Honma Tetsuo、Kitagawa Hiroshi
  • Journal Title: Chemical Communications Volume: 56 Issue: 85 Pages: 12941-12944
  • DOI: 10.1039/d0cc05418f
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] New Insights on the Formation Process and Thermodynamics of the α-Phase PdH(D)x through Direct Enthalpy Measurement of H(D) Dissolution (2020)
  • Author(s): Dekura Shun、Akiba Hiroshi、Yamamuro Osamu、Kobayashi Hirokazu、Maesato Mitsuhiko、Kitagawa Hiroshi
  • Journal Title: The Journal of Physical Chemistry C Volume: 124 Issue: 16 Pages: 8663-8668
  • DOI: 10.1021/acs.jpcc.0c01817
  • Peer Reviewed
• [Journal Article] Magnetic-Field Dependence of Novel Gap Behavior Related to the Quantum-Size Effect (2020)
  • Author(s): Okuno Tomonori、Kinoshita Yuta、Matsuzaki Satoshi、Kitagawa Shunsaku、Ishida Kenji、Hirata Michihiro、Sasaki Takahiko、Kusada Kohei、Kitagawa Hiroshi
  • Journal Title: Journal of the Physical Society of Japan Volume: 89 Issue: 9 Pages: 095002-095002
  • DOI: 10.7566/jpsj.89.095002
  • NAID: 210000158416
  • Peer Reviewed
• [Journal Article] Statistical Evaluation of the Solid-Solution State in Ternary Nanoalloys (2020)
  • Author(s): Tran Xuan Quy、Kono Yoshiki、Yamamoto Tomokazu、Kusada Kohei、Kitagawa Hiroshi、Matsumura Syo
  • Journal Title: The Journal of Physical Chemistry C Volume: 124 Issue: 39 Pages: 21843-21852
  • DOI: 10.1021/acs.jpcc.0c06813
  • Peer Reviewed
• [Journal Article] Chemoselective hydrogenation of heteroarenes and arenes by Pd?Ru?PVP under mild conditions (2020)
  • Author(s): Chaudhari Chandan、Sato Katsutoshi、Nishida Yoshihide、Yamamoto Tomokazu、Toriyama Takaaki、Matsumura Syo、Ikeda Yasuyuki、Terada Kenji、Abe Naoya、Kusuda Kohei、Kitagawa Hiroshi、Nagaoka Katsutoshi
  • Journal Title: RSC Advances Volume: 10 Issue: 72 Pages: 44191-44195
  • DOI: 10.1039/d0ra09981c
  • Peer Reviewed / Open Access
• [Journal Article] Rational Synthesis for a Noble Metal Carbide (2019)
  • Author(s): W. Takuo, K. Kohei, W. Dongshuang, Y. Tomokazu, T. Takaaki, M. Syo, A. Hiroshi, Y. Osamu, I. Kazutaka, O. Toshiya, P. Natalia, C. Yanna, K. Loku S. R., S. Chulho, S. Osami, X. Wei, K. Michihisa, K. Yoshiki, K. Shogo, A. Ryan L., A. Susan M., A. Elvis F., N. Hiroshi, K. Hiroshi
  • Journal Title: Journal of the American Chemical Society Volume: 142 Issue: 3 Pages: 1247-1253
  • DOI: 10.1021/jacs.9b09219
  • Peer Reviewed / Int'l Joint Research
• [Journal Article] Solid-solution alloy nanoparticles of a combination of immiscible Au and Ru with a large gap of reduction potential and their enhanced oxygen evolution reaction performance (2019)
  • Author(s): Quan Zhang, Kohei Kusada, Dongshuang Wu, Naoki Ogiwara, Tomokazu Yamamoto, Takaaki Toriyama, Syo Matsumura, Shogo Kawaguchi, Yoshiki Kubota, Tetsuo Honma, Hiroshi Kitagawa
  • Journal Title: Chemical Science Volume: 印刷中 Issue: 19 Pages: 5133-5137
  • DOI: 10.1039/c9sc00496c
  • Peer Reviewed / Open Access
• [Journal Article] Observation of the Formation Processes of Hexagonal Close-packed and Face-centered Cubic Ru Nanoparticles (2019)
  • Author(s): Araki Naoki、Kusada Kohei、Yoshioka Satoru、Sugiyama Takeharu、Ina Toshiaki、Kitagawa Hiroshi
  • Journal Title: Chemistry Letters Volume: 48 Issue: 9 Pages: 1062-1064
  • DOI: 10.1246/cl.190338
  • NAID: 130007703009
  • Peer Reviewed
• [Journal Article] A Novel Platinum(III)?Platinum(III) Neutral Dimer Complex, Pt2(cdtb)4I2 (cdtb: 4-Cyanodithiobenzoate) (2019)
  • Author(s): Moriyama Hayato、Otsubo Kazuya、Aoki Kentaro、Maesato Mitsuhiko、Sugimoto Kunihisa、Kitagawa Hiroshi
  • Journal Title: Chemistry Letters Volume: 48 Issue: 9 Pages: 1035-1037
  • DOI: 10.1246/cl.190355
  • NAID: 130007703014
  • Peer Reviewed
• [Presentation] Conductive Coordination Networks (2021)
  • Author(s): H. Kitagawa
  • Organizer: International Conference on Advances in Molecular Materials Research
  • Int'l Joint Research / Invited
• [Presentation] ナノ合金技術が切り開く未来 (2021)
  • Author(s): 北川 宏
  • Organizer: SMBCオンラインセミナー,
  • Invited
• [Presentation] Platinum-group-metal high-entropy-alloy nanoparticles for electrocatalysis (2020)
  • Author(s): D. Wu, K. Kusada and H. Kitagawa
  • Organizer: High Entropy Alloy and Complex Solid Solution Nanoparticles for Electrocatalysis
  • Int'l Joint Research
• [Presentation] 非平衡合成による多元素ナノ合金の創製 (2020)
  • Author(s): 北川 宏
  • Organizer: 革新的触媒と反応制御の今後, JST・触媒学会共催オンライン公開シンポジウム
  • Invited
• [Presentation] 非非平衡合成法による多元素ナノ合金粒子の作製と応用 (2020)
  • Author(s): 北川 宏
  • Organizer: 多様な安定相のエンジニアリングの新展開, 応用物理学会秋季学術講演会シンポジウム
  • Invited
• [Presentation] 現代の錬金術：ハイエントロピー効果による革新的ナノ材料の創出 (2020)
  • Author(s): 北川 宏
  • Organizer: 科学技術展望懇談会
  • Invited
• [Presentation] DOS Engineering for New Nano-Materials: Binary to High-Entropy Alloys (2020)
  • Author(s): 北川 宏
  • Organizer: 87th CEMS Colloquium
  • Invited
• [Presentation] Density-of-States Engineering For New Nano-Materials (2020)
  • Author(s): 北川宏
  • Organizer: IISER TVM Frontier Symposium in Chemistry 2020 (FS-CHM 2020)
  • Int'l Joint Research / Invited
• [Presentation] Conductiv Coordination Networkについて (2019)
  • Author(s): 北川宏
  • Organizer: UNIST 2019 Sspring Seminar
  • Int'l Joint Research / Invited
• [Presentation] DOS Engineering for New Green Nano-materials (2019)
  • Author(s): 北川宏
  • Organizer: 鄭州大学国際サマースクール
  • Int'l Joint Research / Invited
• [Presentation] Conductive Coordination Networks (2019)
  • Author(s): 北川宏
  • Organizer: 7TH ASIAN CONFERENCE ON COORDINATION CHEMISTRY ACCC72019
  • Int'l Joint Research / Invited
• [Presentation] Solid -state protonic in Coordination Polymers (2019)
  • Author(s): 北川宏
  • Organizer: 2019 International Conference on Advanced Fibers and Polymer Materials
  • Int'l Joint Research / Invited
• [Patent(Industrial Property Rights)] 担持触媒 (2020)
  • Inventor(s): 草田康平、北川宏、池田泰之、丸子智弘、竹内正史
  • Industrial Property Rights Holder: 草田康平、北川宏、池田泰之、丸子智弘、竹内正史
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2020-035420
  • Filing Date: 2020
• [Patent(Industrial Property Rights)] 合金、合金ナノ粒子の集合体および触媒 (2020)
  • Inventor(s): 北川宏、草田康平、松村晶、山本知一、Tran Xuan Quy
  • Industrial Property Rights Holder: 北川宏、草田康平、松村晶、山本知一、Tran Xuan Quy
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2020-116140
  • Filing Date: 2020
• [Patent(Industrial Property Rights)] 合金、合金ナノ粒子の集合体および触媒 (2020)
  • Inventor(s): 北川宏、小林浩和、洞江祐貴、草田康平、松村晶ra
  • Industrial Property Rights Holder: 北川宏、小林浩和、洞江祐貴、草田康平、松村晶ra
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2020-116142
  • Filing Date: 2020
• [Patent(Industrial Property Rights)] 合金ナノ粒子、合金ナノ粒子の集合体、触媒および合金ナノ粒子の製 造方法 (2020)
  • Inventor(s): 北川宏、草田康平、Wu Dongshuang
  • Industrial Property Rights Holder: 北川宏、草田康平、Wu Dongshuang
  • Industrial Property Rights Type: 特許
  • Industrial Property Number: 2020-116149
  • Filing Date: 2020