Electrodeposition of refractory metals using ionic liquids in an intermediate temperature range

• Project/Area Number: 17H03429
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Material processing/Microstructural control engineering
• Research Institution: Kyoto University
• Principal Investigator: Miyake Masao 京都大学, エネルギー科学研究科, 准教授 (60361648)
• Co-Investigator(Kenkyū-buntansha): 池之上 卓己 京都大学, エネルギー科学研究科, 助教 (00633538) ; 平藤 哲司 京都大学, エネルギー科学研究科, 教授 (70208833)
• Project Period (FY): 2017-04-01 – 2020-03-31
• Project Status: Completed (Fiscal Year 2019)
• Budget Amount: ¥17,550,000 (Direct Cost: ¥13,500,000、Indirect Cost: ¥4,050,000); Fiscal Year 2019: ¥3,900,000 (Direct Cost: ¥3,000,000、Indirect Cost: ¥900,000); Fiscal Year 2018: ¥9,230,000 (Direct Cost: ¥7,100,000、Indirect Cost: ¥2,130,000); Fiscal Year 2017: ¥4,420,000 (Direct Cost: ¥3,400,000、Indirect Cost: ¥1,020,000)
• Keywords: イオン液体 / 電析 / めっき / 高融点金属

Outline of Final Research Achievements

We demonstrated that dense and smooth tungsten alloy films can be electrodeposited using an ionic liquid as a solvent and a novel tungsten salt as an ion source. It was revealed that the resulted alloy films have high corrosion resistance and good mechanical properties. Through this work, we gained knowledge about the dissolution behavior of various tungsten salts in ionic liquids, the electrochemical behavior of tungsten ions in ionic liquids, and the effects of trace amounts of water on them.

Academic Significance and Societal Importance of the Research Achievements

タングステンに代表される高融点金属の潜在的用途は多岐に渡るが、加工が困難であることから、現在は用途が制限されている。本研究により、イオン液体とある種の塩を用いることで、高融点金属元素を含む緻密な合金膜の電析が可能であることが明らかとなった。この電析技術を用いれば、高融点金属（合金）材料を微細構造に成形することが可能であり、高融点金属（合金）材料の適用可能範囲が大幅に拡大されたと考えられる。

Research Products

• [Journal Article] Formation of a photocatalytic WO3 surface layer on electrodeposited Al?W alloy coatings by selective dissolution and heat treatment (2019)
  • Author(s): Higashino Shota、Miyake Masao、Ikenoue Takumi、Hirato Tetsuji
  • Journal Title: Scientific Reports Volume: 9 Issue: 1 Pages: 16008-16008
  • DOI: 10.1038/s41598-019-52178-6
  • NAID: 120006822525
  • Peer Reviewed / Open Access
• [Journal Article] Electrodeposition of Aluminum–Tungsten Alloy Films Using EMIC–AlCl₃–W₆Cl₁₂ Ionic Liquids of Different Compositions (2018)
  • Author(s): Higashino Shota, Miyake Masao, Fujii Hisashi, Takahashi Ayumu, Kasada Ryuta, Hirato Tetsuji
  • Journal Title: MATERIALS TRANSACTIONS Volume: 59 Issue: 6 Pages: 944-949
  • DOI: 10.2320/matertrans.M2018051
  • NAID: 130006744114
  • ISSN: 1345-9678, 1347-5320
  • Year and Date: 2018-06-01
  • Peer Reviewed
• [Journal Article] Electrodeposition of Aluminum-Tungsten Alloy Films Using EMIC-AlCl3-W6Cl12 Ionic Liquids of Different Compositions (2018)
  • Author(s): Shota Higashino, Masao Miyake, Hisashi Fujii, Ayumu Takahashi, Ryuta Kasada, Tetsuji Hirato
  • Journal Title: Materials Transactions Volume: 59
  • NAID: 130006744114
  • Peer Reviewed
• [Presentation] Electrodeposition of All-W Alloy Films Using W(II) Salts Synthesized Using Different Methods (2019)
  • Author(s): Shota Higashino, Masao Miyake, Takumi Ikenoue, and Tetsuji Hirato
  • Organizer: 236th ECS Meeting
  • Int'l Joint Research
• [Presentation] Formation of a photocatalytic WO3 layer on electrodeposited Al-W alloy films by selective leaching and heat treatment (2018)
  • Author(s): Shota Higashino, Masao Miyake, Takumi Ikenoue, Tetsuji Hirato
  • Organizer: Joint International Symposium on Energy Science between Kyoto University and Indian Institute of Science
  • Int'l Joint Research
• [Presentation] 電析アルミニウム-タングステン合金膜の表面脱合金による光触媒層の形成 (2018)
  • Author(s): 東野 昭太，三宅 正男，池之上 卓己，平藤 哲司
  • Organizer: 表面技術協会
• [Presentation] Electrodeposition of Al-W Alloys and Surface Modification by Anodization (2018)
  • Author(s): Shota Higashino, Masao Miyake, Takumi Ikenoue, and Tetsuji Hirato
  • Organizer: 22nd Topical Meeting of the International Society of Electrochemistry
• [Presentation] Electrodeposition and Anodization of Al-W Alloy Films (2017)
  • Author(s): Shota Higashino, Masao Miyake, Takumi Ikenoue, and Tetsuji Hirato
  • Organizer: 232nd ECS Meeting National Harbor
  • Int'l Joint Research