A direct synthesis of Si-nanowires on 3D porous graphene as a high performance anode material for Li-ion batteries

Abstract

Silicon nanowires (SiNWs) have been successfully synthesized on a three-dimensional porous graphene foam (GF) via chemical vapor deposition (CVD). The unique porous nanoarchitecture of the three-dimensional graphene network enhances the electrical conductivity and provides improved Si-mass loadings. The obtained GF/SiNWs composite, with Si mass loadings of >0.3 mg cm⁻² shows high gravimetric and areal capacities, as well as comparable cycle life as an anode material in Li-ion battery. An alumina coating (ALD) of SiNWs also improved the cycle life and rate capability. This facile direct synthesis method of a 3D porous architecture of the GF/SiNWs composite demonstrates a new approach to improve the electrochemical performances of Si-based anode materials for Li-ion batteries.