Abstract
In contrast to monofunctional electrocatalysts for oxygen evolution reaction (OER), hydrogen evolution reaction (HER) or oxygen reduction reaction (ORR), trifunctional catalysts for simultaneously generating H-2, O-2 and H2O provide a crucial means for improving the overall efficiency of water electrolysis. Herein we present a series of nonnoble metal [M = Fe(III), Co(II), Ni(II)]-nitrogen co-doped oxidized graphite rods (M-N/OGRs) that function as in situ working electrodes for tri-functional OER, HER and ORR electrocatalysis. The enhanced performance of the hybrid catalysts appear mostly associated with dual active site mechanisms originating from the synergic effects of M-N/Co-doped on the surface of the OGR. Our findings suggest that, the development of multifunctional electrocatalysts with optimal catalytic activity using transition metals and nitrogen doped OGR opens new doors for in situ synthesized electrocatalysts for use in clean electrochemical energy storage and conversion technologies.