钾离子电池过渡金属氧化物正极材料:研究进展与设计策略OA

Potassium-ion batteries(PIBs)have emerged as promising candidates for large-scale energy storage systems,owing to the abundant potassium resources and electrochemical properties similar to those of lithium-ion systems.Cathode materials play a pivotal role in determining the overall performance of PIBs.Among them,transition metal oxides(TMOs)have attracted extensive research interest due to their high theoretical capacity,suitable operating voltage,and tunable crystal structures.However,the relatively large ionic radius of K+often leads to significant volume variation and anisotropic strain during(de)intercalation,which induces irreversible phase transitions,severe lattice distortion,and structural collapse.In addition,the Jahn-Teller effect associated with transition-metal ions such as Mn3+further aggravates local structural distortion and triggers transition metal dissolution,severely limiting the cycling stability and energy density of TMO cathodes.These issues underscore the importance of rational material design and interface regulation to achieve stable electrochemical performance.This review systematically summarizes the recent progress in TMO cathode materials for PIBs,encompassing evaluation metrics and synthesis methods.A variety of modification strategies,including elemental doping,surface coating,and multi-scale structural design,have been developed to modulate lattice parameters and defects,suppress phase transitions,and enhance ionic conductivity,operating voltage,structural stability,and cycling endurance.Among these approaches,P2/P3 biphasic integration and high-entropy doping,for example,have been shown to effectively inhibit Jahn-Teller distortion and volume change,thereby enabling long-term cyclability.In addition,the combination of in situ characterization and theoretical calculations has significantly deepened the understanding of K+storage mechanisms and structure-performance relationships.Notwithstanding the substantial progress achieved,several critical challenges persist.These include capacity enhancement and structural stability optimization,cycle life improvement and the formulation of integrated strategies,cathode-electrolyte interphase engineering,the development of composite materials and hybrid systems,ensuring manufacturing consistency and scalability,advancing theoretical modeling and computational guidance,as well as leveraging artificial intelligence(AI)-assisted material design and prediction.Future efforts should focus on developing novel structural motifs,optimizing electrode/electrolyte interfaces,advancing sustainable manufacturing processes,and integrating AI-guided material design.This review provides a comprehensive overview of mechanistic strategies and recent progress,offering valuable insights for the rational design of high-performance PIBs suitable for practical applications in large-scale energy storage and next-generation energy storage applications.