Structured spinel oxide positive electrodes of magnesium rechargeable batteries: High rate performance and high cyclability by interconnected bimodal pores and vanadium oxide coating

JOURNAL OF ALLOYS AND COMPOUNDS

卷:816

Article

Ishii, Kanji¹  Doi, Shunsuke¹  Ise, Ryuta¹  Mandai, Toshihiko^2,3  Oaki, Yuya¹  Yagi, Shunsuke⁴  Imai, Hiroaki¹ 

[1] Keio Univ, Fac Sci & Technol, Dept Appl Chem, Kohoku Ku, 3-14-1 Hiyoshi, Yokohama, Kanagawa 2238522, Japan

[2] NIMS, Ctr Res Energy & Environm Mat, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan

[3] Iwate Univ, Fac Sci & Engn, Dept Chem & Biol Sci, 4-3-5 Ueda, Morioka, Iwate 0208551, Japan

[4] Univ Tokyo, Inst Ind Sci, Meguro Ku, 4-6-1 Komaba, Tokyo 1538505, Japan

关键词: Morphology control;    Coating;    Polymerized complex method;    Mg battery;    Positive electrode;   

DOI  :  10.1016/j.jallcom.2019.152556

来源: Elsevier

【 摘 要 】

A structured spinel oxide as a positive-electrode active material for magnesium rechargeable batteries was produced using a propylene-oxide-driven sol-gel method and subsequent vanadium oxide coating. Porous frameworks consisting of MgMn2O4 nanoparticles having diameters of similar to 10 nm exhibited a large specific surface area of similar to 150 m(2) g(-1) and interconnected bimodal pores distributed in the micrometer (1-10 mu m) and nanometer (10-100 nm) regions. Hierarchical conduction paths constructed by mixing the porous frameworks with carbon nanoparticles reduced the overpotential for the insertion and extraction of magnesium ions and increased the redox capacity in an ionic-liquid electrolyte system. Moreover, the surface coating of vanadium oxide on the spinel oxide nanoparticles enhanced the extraction of magnesium ions and suppressed the decomposition of the electrolyte. The electrochemical properties, such as the capacities, rate capabilities, and cyclabilities, of the positive electrodes were largely improved by the structured spinel oxide frameworks. (C) 2019 Elsevier B.V. All rights reserved.

【 授权许可】

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