Enhanced K-storage boosted by compatible ester-based electrolyte for COFs-derived non-graphitic carbon

Abstract

Effectiveness of non-graphitic carbon materials with disordered structures in potassium storage has promote it as high-performance K-storage anodes of potassium-ion batteries (PIBs). However, there are defects that have not been adequately addressed, in which unstable K-storage performance along with sluggish reaction kinetics usually result from the severe interfacial side reactions and large K+ radius. Herein, rational electrolyte regulation has been treated as a promising strategy to achieve superior K-storage performance for the developed non-graphitic carbon from covalent-organic-frameworks (COFs). Specifically, it give rise to excellent cycle stability of 250 mAh/g after 500 cycles at 50 mA/g and high rate performance of 170 mAh/g after 400 cycles at 1000 mA/g, respectively. The boosted K-storage performance is ascribed to the fast interfacial reaction kinetics dependent on inorganic-rich and stable solid electrolyte interphase (SEI) that derived from the aggregates-dominated solvation structures in the optimized concentrated electrolyte. These findings suggest opens up an effective strategy from electrolyte chemistry that significantly affected SEI for advancing high-performance PIBs.