Progress and strategies in transition metal chalcogenides as anode for potassium-ion batteries

Rechargeable potassium-ion batteries (PIBs) are attractive alternatives to lithium-ion counterparts for large-scale applications due to the low cost and abundant availability of potassium resources. Transition metal chalcogenides (TMCs) have emerged as potential PIBs anodes owing to their diverse compositions, abundance, low cost, robustness, and high theoretical capacities. However, TMCs face challenges such as severe volume changes during potassiation/depotassiation, inadequate conductivity, and scalability issues. Consequently, various traditional and unconventional techniques have been developed to mitigate these challenges and obtain highquality electrode materials for practical applications. This review summarizes the recent progress and strategies employed to address the challenges associated with TMC as anode materials for PIBs. Firstly, challenges and modification strategies of TMCs anode have been investigated. Then, effective synthesis approaches of TMCs have been reviewed. As important TMCs, metal sulfides and metal selenides as anode of PIBs have been comprehensively summarized. Finally, several outlooks and perspectives for the improvement of TMCs anode materials have been outlined.