Element-tailored quenching methods: Phase-defective K0.5Mn1-xCrxO2 cathode materials for potassium ion batteries

Abstract

Potassium-ion batteries (PIBs) are emerging as a promising next-generation energy storage system due to their high economic efficiency and theoretical energy density. Among various cathode materials, KMnO-based cathode materials have garnered significant attention due to their high energy density and industrial feasibility. In this work, A P3-type KMnCrO cathode material was synthesized using a target-elements tailoring quenching method. By strategically substituting targeted elements and employing tailored quenching techniques, it can effectively alleviate Jahn-Teller distortion and suppress phase transitions, enhancing the material structural stability. The synthesized KMnCrO cathode material demonstrated excellent cycling stability of retaining 70 % specific capacity after 300 cycles at a current density of 500 mA g. This work breaks out the traditional solid-phase sintering preparation method and provides a new solution for the future preparation of other structurally stable high-performance layered oxides with excellent rate performance for potassium ion batteries.