Reduced graphene oxide/CoSe nanocomposites: Hydrothermal synthesis and their enhanced electrocatalytic activity

Reduced graphene oxide (RGO)/CoSe nanocomposites were synthesized by self-assembly of CoSe/DETA (DETA: diethylenetriamine) onto the surface of graphene oxide (GO), followed by subsequent chemical reduction of GO during a hydrothermal process. The as-synthesized products were characterized by powder X-ray diffraction, energy dispersive X-ray spectroscopy, Raman spectra, scanning electron microscopy, and transmission electron microscopy. The morphology of the CoSe on the RGO nanosheets can be well controlled by adjusting the reaction time during the hydrothermal process. The catalytic activities of the RGO/CoSe nanocomposites were investigated for oxygen evolution reaction (OER) in alkaline conditions. It was found that the as-formed RGO/CoSe nanocomposites show higher catalytic activity compared with the unsupported CoSe. In addition, the loading amounts and morphologies of CoSe on RGO sheets have a great influence on the catalytic performance of RGO/CoSe. Our studies raise promising possibilities for designing effective OER electrocatalysts for energy conversion. © 2013 Springer Science+Business Media New York.