Plasma-assisted synthesis of Ni4Mo/MoO2 @carbon nanotubes with multiphase-interface for high-performance overall water splitting electrocatalysis

The rational design of significant bifunctional electrocatalysts for water-splitting is crucial for the production of sustainable hydrogen fuel. Constructing multiphase interfaces is a powerful method to increase active species for bifunctional electrocatalysts. Herein, an efficient water splitting electrocatalyst based on the Ni4Mo/MoO2/C porous nanosheets is successfully reduced by the NiMoO4·nH2O with a simple plasma process in the methane atmosphere. The optimized Ni4Mo/MoO2/C-10 electrocatalyst shows excellent electrocatalytic performances for overall water splitting, which is affirmed by the significantly low overpotentials of 77 mV for hydrogen evolution reaction (HER), 275 mV for oxygen evolution reaction (OER), and 1.57 V for water splitting at 10 mA cm−2. What’s more, the Ni4Mo/MoO2/C exhibits superior cycling durability for water splitting. DFT calculations illustrate that the resulting Ni4Mo/MoO2/C with multiphase interfaces can accelerate the electron transfer, which can optimize H* adsorption and desorption, thereby reducing the hydrogen adsorption free energy (|ΔGH*|) to improve the reaction kinetics. Our work demonstrates that the synthesis of transition metal-based multiphase interfaces by plasma treatment can effectively enhance the water splitting performances.