Fabrication of Photoelectric Mn Oxide for Enhancing the High Capacity and Elucidation of Ion Insertion and Desorption Mechanisms

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K05007
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 26020:Inorganic materials and properties-related
• Research Institution: Kanto Gakuin University
• Principal Investigator: Tomono Kazuaki 関東学院大学, 理工学部, 准教授 (40516449)
• Co-Investigator(Kenkyū-buntansha): 隅本 倫徳 山口大学, 大学院創成科学研究科, 准教授 (40414007)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 層状化合物 / 層間金属錯体 / 光電流 / キャパシタ / イオン電池 / 挿入脱離機構

Outline of Final Research Achievements

Two-type layered MnO2 films with [Co(en)3] complexes and (C12H25)2(CH3)2N ions as interlayer ions were prepared and the specific capacitance of the obtained films were measured. When the MnO2 film with (C12H25)2(CH3)2N ion as interlayer ion was formed on the MnO2 film with [Co(en)3] complexes, the deintercalation of the [Co(en)3] complex was suppressed, and its initial capacitance of 136.7 F/g ((C12H25)2(CH3)2N@MnO2/[Co(en)3]@MnO2) exhibited higher than that of the reverse layered MnO2 films ([Co(en)3]@MnO2/(C12H25)2(CH3)2N@MnO2). Moreover, when the optimized film was irradiated with light (460 nm) for 30 min, the initial capacitance of 757.9 F/g was observed, which was almost five times higher than the film without light irradiation. Electrochemical properties of the optimized film were measured by systematically changing the alkyl-chain length of the interlayer ion and MV concentration of the electrolyte. The capacitance was successfully improved by photo irradiation and MV addition.

Free Research Field

無機分析・電気化学システム

Academic Significance and Societal Importance of the Research Achievements

層間に金属錯体を有する層状マンガン酸化物が高い比容量をもつこと，そのメカニズムを明らかにするには今後もさらなる研究が必要となるが，本研究により層間金属錯体の脱離抑制方法を明らかにしたことは学術的意義が高いといえる。また，光照射や電子伝達物質の操作を加えることで，非常に高い比容量と安定性を達成することができた。マンガン酸化物の電気二重層キャパシタとしての理論値の72%に達しており社会的意義も高い。今後は，本系のキャパシタと電池の両方の側面から詳細な電子伝達メカニズムを電気化学・分光分析を通して明らかにする。