Graphene and cobalt phosphide nanowire composite as an anode material for high performance lithium-ion batteries

The synthesis of a composite of cobalt phosphide nanowires and reduced graphene oxide (denoted CoP/RGO) via a facile hydrothermal method combined with a subsequent annealing step is reported. The resulting composite presents large specific surface area and enhanced conductivity, which can effectively facilitate charge transport and accommodates variations in volume during the lithiation/de-lithiation processes. As a result, the CoP/RGO nanocomposite manifests a high reversible specific capacity of 960 mA·h·g^–1 over 200 cycles at a current density of 0.2 A·g^–1 (297 mA·h·g^–1 over 10,000 cycles at a current density of 20 A·g^–1) and excellent rate capability (424 mA·h·g^–1 at a current density of 10 A·g^–1). [Figure not available: see fulltext.]