Construction of polar spaces by metal complex assembly and control of ion rectification properties

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18936
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 32:Physical chemistry, functional solid state chemistry, and related fields
• Research Institution: Kyushu University
• Principal Investigator: Ohtani Ryo 九州大学, 理学研究院, 准教授 (30733729)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 極性 / シアノ / イオン伝導

Outline of Final Research Achievements

In this study, we developed a novel polar material where protons migrate in a polar framework constructed by cyanido metal complexes of [MnN(CN)4]2-, and found functionality in which ferroelectricity and proton conductivity properties are strongly correlated. The contribution of protons, which are the conductive species, to the polarization of the ferroelectric crystal led to the development of a ferroelectric material exhibiting a polarization value approximately 1000 times larger than that of conventional polar materials. We also revealed the unique structural property of the compound in which spatial inversion symmetry is broken in response to water vapor.

Free Research Field

錯体化学

Academic Significance and Societal Importance of the Research Achievements

これまで両立しないと考えられていたイオン伝導性と強誘電特性が相関することで、イオン整流特性に基づく巨大分極現象が生じることを発見した。更なる開発が望まれている極性材料に、イオン伝導を用いる全く新しい設計指針を示した。