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

• Published in: Materials today chemistry Vol. 40
• Main Authors: Liu, Zhaomeng, Li, Shangzhuo, Mu, Jianjia, Zhao, Lu-Kang, Gao, Xuan-Wen, Gu, Qinfen, Wang, Xuan-Chen, Chen, Hong, Luo, Wen-Bin
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.09.2024
• Subjects: Cathode materials; Crystal anisotropy; Layer-structured oxide; Potassium ion battery; Quenching; Layer-structured oxide; Crystal anisotropy; Cathode materials; Potassium ion battery; Quenching
• ISSN: 2468-5194; 2468-5194
• DOI: 10.1016/j.mtchem.2024.102251

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, K0·5MnO2-based cathode materials have garnered significant attention due to their high energy density and industrial feasibility. In this work, A P3-type K0.5Mn1-xCrxO2 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 K0.5Mn1-xCrxO2 cathode material demonstrated excellent cycling stability of retaining 70 % specific capacity after 300 cycles at a current density of 500 mA g−1. 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. In this work, a P3-type K0.5Mn1-xCrxO2 cathode material was synthesized using a target-elements tailoring quenching method. The quenching process promoted the formation of smaller and more uniform grains, improving structural homogeneity and reducing grain boundary effects. The synthesized K0.5Mn1-xCrxO2 cathode material demonstrated excellent cycling stability of retaining 70 % specific capacity after 300 cycles at a current density of 500 mA g−1. [Display omitted] •P3-type K0.5Mn1-xCrxO2 cathode materials with defective structures were synthesized by quenching instead of conventional solid-phase method.•The synergistic effect arising from the presence of defective phases and grain refinement effects effectively mitigates interlayer sliding and suppresses irreversible phase transitions.•K0.5Mn1-xCrxO2 exhibits excellent specific capacity of 65.51 mAh g−1 after 350 cycles at 200 mA g−1.