Constructing highly active interface between layered Ni(OH)2 and porous Mo2N for efficient electrocatalytic oxygen evolution reaction.

Layered Ni(OH) 2 materials are cheap and efficient electrocatalyst for water splitting. However, pristine Ni(OH) 2 materials usually show poor activity due to the low activity sites and poor conductivity in electrochemical reactions. Herein, layered Ni(OH) 2 nanosheets are grown on the porous Mo 2 N particles for improved interfacial active sites and enhanced conductivity in the oxygen evolution reaction (OER). The OER overpotential of the optimized Mo 2 N/Ni(OH) 2 composite material is distinctly reduced compared with pristine Ni(OH) 2. In addition, the optimized Mo 2 N/Ni(OH) 2 composite material exhibits favorable durability in alkaline electrolyte. Further electrochemical investigation reveals that the Mo 2 N/Ni(OH) 2 composite materials produce increased charge transfer capability and electrochemical active surface area. Theoretical calculation study demonstrates that a redistribution of electron occurred at the interface of Ni(OH) 2 and Mo 2 N, which results in the decrease of energy barrier for the adsorption of OER reactive intermediates at the interfacial atoms. The enhanced performance of OER is thus mainly come from the constructed interface between layered Ni(OH) 2 and porous Mo 2 N. This work gives a feasible method to develop cheap and efficient electrocatalysts for water splitting. [Display omitted] • The Ni(OH) 2 composites with porous Mo 2 N for reduced electrocatalytic OER overpotential and enhanced stability. • The Ni(OH) 2 /Mo 2 N composite materials show distinctly improved electrochemical active areas and conductivity. • DFT calculations reveal the retribution of electrons densities at interface, decreasing the OER energy barrier. [ABSTRACT FROM AUTHOR]