The rational design for the material with high proton conductivity and low dependence on humidity

2020 Fiscal Year Final Research Report

• Project/Area Number: 19K15351
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 27020:Chemical reaction and process system engineering-related
• Research Institution: Kyoto University
• Principal Investigator: Ogawa Takaya 京都大学, エネルギー科学研究科, 特定助教 (90748550)
• Project Period (FY): 2019-04-01 – 2021-03-31
• Keywords: プロトン伝導

Outline of Final Research Achievements

The effect of various acids and water on the conditions under which the packed-acid mechanism occurs in different proton acceptors was investigated. Quantum chemical calculations show that as the pKa of the proton acceptor's covalent acid increases, the proton donor must use a lower acid pKa to prevent the acid interaction between the proton donors from extending to distant hydrogen bonds. In addition, when the pKa of the co-beneficial acid is high, the acid interaction by the co-beneficial acid is also small. In other words, the Packed-acid mechanism is enhanced by using a proton acceptor with low proton acceptor (basicity).

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

本研究により、Packed-acid mechanismをより引き起こすために重要な酸・塩基の選定に重要なパラメーターがわかり、Packed-acid mechanismが支配的に起こるプロトン伝導固体材料を開発するための設計指針を得ることができた。一方で、実験的なプロトン伝導度は、溶液の粘度と酸解離度に大きく影響されていることがわかった。また、酸高密度溶液では同位体効果が大きく現れることが実験的に示された。トンネル効果をより引き起こす条件を特定できれば、、通常なら起こり得ない難しい反応も酸・塩基溶液の相互作用に基づくトンネル効果で促進できることが示唆された。