Functional advancement of complex hydrides as solid-state ionic conductor by structural optimization

2018 Fiscal Year Final Research Report

• Project/Area Number: 16H04513
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Structural/Functional materials
• Research Institution: Kwansei Gakuin University
• Principal Investigator: Matsuo Motoaki 関西学院大学, 理工学部, 准教授 (20509038)
• Research Collaborator: Orimo Shin-ichi
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 錯体水素化物 / イオン伝導

Outline of Final Research Achievements

Hydro-closo-borates composed of the [B12H12]2－ closo-borate anions exhibit superionic conductivities on the order of 0.1 S/cm after the order-disorder transitions. From the application point of view, it is highly desirable to enhance the conductivities at room temperature. In this study, we have found out combining [B12H12]2－ with [NH2]- and partial dehydrogenation are effective in modifying the conductivities of hydro-closo-borates. Na2B12H12 + NaNH2 shows the highest sodium ionic conductivity of 1×10(-6) S/cm at room temperature in this system. In the case of Na2B10H10, the conductivity is also increased to 3×10(-5) S/cm when mixed with NaNH2 at molar ratio of 3:1. Moreover, the conductivity of Li2B12H12 increases to 2×10(-5) S/cm from 6×10(-7) S/cm by partial dehydrogenation.

Free Research Field

エネルギー機能材料としての水素化物の開発

Academic Significance and Societal Importance of the Research Achievements

クロソ系錯体水素化物の相転移温度以下でのイオン伝導率を改善するという目標を達成することができた。その中でも部分脱水素化量制御によるアプローチは、水素化物特有のものであり、国内外の他のグループに先行して本研究で初めて着眼した材料設計指針である。今後錯体水素化物での高速イオン伝導機能を飛躍的に発展させ高エネルギー密度の全固体二次電池の実現を後押するとともに、“水素化物でのイオニクス”分野の学理探求に貢献する成果と言える。