Interfacial coupled design of epitaxial Graphene@SiC Schottky junction with built-in electric field for high-performance anodes of lithium ion batteries

Abstract

Abstract In-situ epitaxial graphene (EG) strategy is adopted to activate the electrochemically inactive silicon carbide (SiC) by constructing Schottky junction for high-performance anode of lithium-ion battery (LIB). Raman and Hall measurements confirm the high quality and electronic mobility of EG. Refined structural characterization (XPS and XANES) and theoretical analysis indicate that the interfacial coupled structure exhibits Schottky junction with an inherent built-in electric field, and the strong interfacial Si–C interaction could reinforce the interfacial coupling. This prototype can systematically comprehend interfacial electronic properties and transport mechanisms. As a proof-of-concept study, this interfacially designed Schottky junction is demonstrated to promote both the surface electron densities and charge carriers transportation efficiency for LIB anodes. Even at 10.0 A g−1, the EG@SiC anode can still deliver a capacity of 322.1 mA h g−1. The ex-situ XRD, HRTEM, and XPS analysis confirm the reversible intercalation reaction mechanism and excellent structural stability. The proposed strategy of constructing Schottky junction through interlayer engineering can construct advanced SiC-based electrodes for high-performance rechargeable batteries.