In-situ construction of edge site-enriched VS4/graphene hybrids toward high-performance lithium storage

Abstract

In-situ construction of edge site-enriched transition metal sulfides coupled graphene hybrids holds an effective strategy for high-performance lithium-ion storage. Here, a hybrid architecture with edge site-enriched VS4 electroactive species anchored on graphene sheet is tailor-made as an ideal host for Li+ via a simple in-situ assembly process. The etching effect is an indispensable factor in the formation of hybrid structure with ultra-rich edge sites, which makes a positive contribution to the surface-structure activity. The integrated hybrids not only guarantee a high utilization of electroactive species and fast reaction kinetics, but also open up synergistic electrochemical properties. Thus, the optimized VS4/Graphene electrodes exhibit uplifting specific capacity (1220 mAh g−1 at 1 A g−1), superb rate (476 mAh g−1 at 20 A g−1), and excellent cycling durability (100% maintains over 1000 cycles at 10 A g−1). In addition, an irreversible amorphous transition and redox reaction mechanism in the first cycle have been revealed. This work is expected to expound a feasible strategy for the progress of energy storage system.