Graphene-wrapped Ni2P materials: a 3D porous architecture with improved electrochemical performance

Abstract

Ni2P/graphene hybrid with a 3D architecture has been successfully accomplished through a series of controlled chemical processes. In contrast to random mixture of Ni2P nanoparticles and graphene nanosheets, the architecture hybrid exhibits superior electrochemical stability because the Ni2P nanoparticles are firmly riveted on the graphene sheets. The 3D graphene network enhances the electrical conductivity over the 2D nanostructure. As anode materials for lithium-ion batteries, the graphene-wrapped Ni2P nanoparticles can deliver a reversible capacity of ~400 mAh g−1 after 30 cycles with nearly no fading and also exhibit a good rate performance. The graphene network can serve as a conducting network for fast electron transfer from all directions between the active materials and charge collector, and better buffer spaces to accommodate the volume expansion/contraction during discharge/charge process, which can be considered to contribute to the remarkable cyclic stability, thereby pointing to a new synthetic route to hybridizing graphene with active materials for advanced lithium ion batteries.