Synthesis of copper naphthalocyanine/graphene oxide composites as anode materials for lithium-ion batteries

Naphthalocyanine and its derivatives are new types of functional materials with wide application prospects. This paper discusses the synthesis of copper tetra tert-butyl-naphthalocyanine (CuNc) and analyses its molecular and electronic structure. Next, CuNc is combined with graphene oxide (GO) through π-π interaction and then pyrolyzed to form a CuNc/GO composite. A systematic investigation of the morphology, structure, composition and properties of CuNc/GO revealed that N-doped graphene is decorated with CuO particles. The electrochemical properties of CuNc/GO are compared with those of directly pyrolysed CuNc. The prepared CuNc/GO (1 : 1) electrode shows a large specific capacity (655.1 mA h g^-1) after 100 cycles at 100 mA g^-1. Its high capacity, enhanced cycling stability and strong rate performance are attributed to the synergetic effect of N-doped graphene and CuO particles. Besides expanding the use of naphthalocyanine compounds, this work presents a promising candidate material for lithium-ion battery anodes.