Synthesis of MoO3/N, P co-doped carbon for electrochemical water splitting

Abstract

Catalytic water splitting into H2 is a prospective way to alleviate the fossil fuels crisis. To date, α-MoO3 nanostructures show the low activity in water electrolysis reaction because of their poor conductive ability. The rational design of α-MoO3 with tunable electron structure is greatly desired to promote electrocatalytic performance. Herein, we utilize a facile one-pot method to prepare MoO3/N, P co-doped carbon sheets (MoO3/NPC). Carbon sheets are regulated by N and P doping, which are generated by thermal pyrolysis of melamine phosphate. Accordingly, the partial reduction of MoO3 nanosheets is elaborated by coordinative unsaturated Mo5+ sites. Experimental investigations show that MoO3 nanosheets are anchored on N and P co-doped carbon sheets. The electrochemical studies indicate that MoO3/NPC presents excellent water oxidation reactivity with 231 mV@10 mA/cm2, which is superior to RuO2 (283 mV). In comparison to α-MoO3 nanosheets (204 mV), the enhanced water reduction reactivity is achieved on MoO3/NPC with 144 mV at 10 mA/cm2. Serving as the bi-functional catalysts to drive water splitting, MoO3/NPC exhibits a low voltage of 1.59 V at 10 mA/cm2. Our work highlights that heteroatom engineering could mediate the electron state of MoO3 and thereby accelerate water splitting rate.