Rational design of carbon materials as anodes for potassium-ion batteries

Abstract

The ever-increasing demand for clean energy has attracted considerable attention on the scalable and affordable potassium-ion batteries (PIBs) while one of the challenges hampering the development of rechargeable PIBs is attributed to the lack of suitable anode materials. This problem necessitates the design of cost-effective, nontoxic, and highly stable anodes with high specific capacity. In this review, we present the recent advances in rational design of carbon materials for developing such anodes for PIBs. Firstly, graphite, graphene, and disordered carbon as anodes for PIBs and their practical problems are comprehensively summarized based on sp2 hybridization. Secondly, the potassium storage mechanism corresponding to the intercalation and adsorption mechanism for guiding rational design of carbon materials is discussed, followed by illustrations of how the design of heteroatom doping, porous structure, and carbon composites provides fundamental insights into high conductivity, structural integrity, and enhanced electrochemical activity. Finally, conclusions and perspectives are pointed out for developing the next-generation carbon anodes for PIBs with high energy density and excellent cycling stability.