Relationship between Cation Transport Abilities and Inner-structure of the Boundary-free Porous Coordination Polymer Film

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K05523
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 34010:Inorganic/coordination chemistry-related
• Research Institution: Yamagata University
• Principal Investigator: Ishizaki Manabu 山形大学, 理学部, 講師 (60610334)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: プルシアンブルー / 電気化学 / ナノ粒子 / イオン伝導 / 電子伝導

Outline of Final Research Achievements

The Prussian blue (PB) and its analogues (PBA), which are porous coordination polymer nanoparticles, are synthesized with various internal structures and particle sizes by controlling the synthesis conditions. And, the as-prepared PB/PBA are surface-modified by ferrocyanide ions for dispersion into water and cation doping.
The proton conductivities of the PB/PBA are measured by using pellet-type cells and spin-coated thin film. A spin-coated thin film of PB is suitable for the estimation of grain-boundary free proton conductivity. Furthermore, by using a sandwich cell with porous CNT film, I measured unique current-voltage (I-V) properties, that is resistance switching behavior by applied potential and succeeded in observing the cation conductivity in PBA influencing the hydrated state. The Li-ion conduction pathway in CuPBA with Jahn-Teller structural strain is visualized from theoretical calculations.

Free Research Field

錯体化学、ナノ材料科学

Academic Significance and Societal Importance of the Research Achievements

PB及びPBAは、イオン伝導体や電池活物質材として利用が期待されている。しかし、内部構造が与える電池特性への影響は十分に理解されていない。この解明が機能の向上・制御に重要となる。本研究では、外部環境に依存したイオン伝導度の測定に成功した。
また、カーボンナノチューブ膜の多孔性と光透過性を生かした機能探索を行った。本技術は、これまで観測できなった高抵抗体の機能探索に有効である。PB/PBAに限らず、外部環境に依存する機能や電気特性による色変化の観測など、他の機能性材料にも応用可能な新たな機能評価法を提案できた。