A Platelet Graphitic Nanofiber-Carbon Nanotube Hybrid for Efficient Oxygen Evolution Reaction

Carbon nanostructures with a high-density of active sites are needed as catalysts for the oxygen evolution reaction (OER). Here we report a platelet graphitic nanofiber-carbon nanotube (PGNF-CNT) hybrid electrocatalyst prepared by chemical vapor deposition. The material is composed of interconnected CNTs and nanofibers consisting of graphitized carbon layers stacked at different angles to the fiber axis with a large number of exposed edges. These unique structural characteristics give the hybrid a high density of active sites, fast electron transfer and a large number of mass transport paths. As a result, the material has an excellent electrocatalytic activity for OER with an overpotential of 0.28V at a current density of 10mAcm(-2), which is much better than those of Ir/C and previously-reported carbonaceous catalysts.