Purely Inorganic {P₄Mo₆O₃₁}-Based Polyoxometalates Materials Enabling Electrochemical Energy Storage

Abstract

Polyoxometalates (POMs) are considered highly suitable for electrochemical energy storage due to their advantageous structural and electrochemical features. As inorganic molecular clusters, POMs exhibit high thermal and chemical stability, tunable redox potentials, and a wide range of compositions, making them attractive for use in electrochemical storage devices. This work systematically explores the unique advantages of POMs-based materials, including their redox reactions and charge storage mechanisms. The introduction of conductive polymers into electrochemical devices shows remarkably enhanced performance, and the assembled solid-state capacitor 1-CC@PANI-SC achieved a maximum specific capacitance of 86.8 mAh g⁻¹, an energy density of 14.16 Wh kg⁻¹ with power density of 802.57 W kg⁻¹. This study provides a promising insight for the design and synthesis of purely inorganic POMs and applications in energy storage devices.

Keywords

polyoxometalates / proton conduction / solid-state capacitors

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2025 The Author(s). Electron published by Harbin Institute of Technology and John Wiley & Sons Australia, Ltd.