In-situ formation of Cu–Ni cyano-bridged coordination polymer on graphene oxide nanosheets and their thermal conversion

Abstract

Abstract This work reports a facile approach for the synthesis of a novel hybrid material consisting of Cu–Ni cyano-bridged coordination polymer (CP) nanoflakes and graphene oxide (GO) nanosheets (CuCNNi/GO hybrid). The functional groups present on the GO nanosheets (e.g., carboxylic acid and hydroxyl groups) can promote interactions with Cu2+ ions. The electrostatic interactions with positively-charged Cu2+ ions causes the surface of the GO nanosheets to become positively charged and the addition of [Ni(CN)4]2- initializes the formation and growth of CuCNNi nanoflakes on the GO surface. The thermal treatment of the CuCNNi/GO hybrid at 300–600 °C results in their conversion to porous Cu–Ni oxide/GO hybrids. As the GO nanosheets can prevent the rapid crystallization and fusion of metal oxides during the calcination process, an optimized Cu–Ni oxide/GO composite with a high surface area of 145 m2 g1 can be realized. More importantly, this specific surface area is higher than that of individual Cu–Ni oxide nanoflakes (11.1 m2 g−1). It is expected that this approach can be extended for the preparation of other CP-derived metal oxide/GO hybrids for a wide variety of functional applications.