Electrode Properties of Todorokite-type Tunnel-structured Manganese Oxide for Calcium Secondary Batteries

  • Shinya Suzuki School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
  • Tsubasa Kato School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
  • Hidetoshi Kawabata School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan
  • Masaru Miyayama School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan

Abstract

The electrode properties of todorokite-type tunnel-structured manganese oxides (TodMO) were examined for their potential use as cathode materials in calcium batteries. TodMO with a chemical composition of Mg0.19Na0.07MnO2·0.37H2O was prepared through hydrothermal treatment of layer-structured manganese oxide using magnesium ions as interlayer guest ions. The TodMO exhibited a dis-charge and charge capacity of 100 and 80 mAh g−1, respectively, at a relatively large current density of 100 mA g−1. The reaction mecha-nism was studied in detail using X-ray absorption spectroscopy measurements. Consequently, it became clear that the newly formed Mn3+-compound converted from TodMO is responsible for the reversible capacity.

Published
2016-07-02
Section
Full Articles