Excellent Bifunctional Water Electrolysis Activities of α-MoO3/AC Nanocomposites

Abstract

Electrocatalytic water splitting is a cost-effective and environment-friendly technique for producing oxygen and hydrogen through the oxygen/hydrogen evolution reaction (OER/HER). Developing the highly active and stable electrocatalyst, particularly for bifunctional water electrolysis (i.e., both OER and HER), is still a formidable challenge. Herein, we demonstrated the enhanced bifunctional water splitting activities by utilizing the molybdenum trioxide-anchored activated carbon (MoO3/AC) nanocomposites. The MoO3/AC samples were fabricated by the ultrasonication method using sol-gel synthesized MoO3 and biomass-derived AC, and they displayed a nanostreusel-like morphology with spherical MoO3 nanoparticle-decorated AC nanosheets. For the water electrolysis test, the MoO3/AC nanocomposites exhibited the excellent bifunctional electrocatalytic OER and HER performances with low overpotential and small Tafel slope values. Through analyzing the material characteristics and the electrochemical properties of MoO3/AC, it was found that the superb bifunctional OER-HER activities were attributed to the synergistic effects from the hybridization of highly conductive AC and electrochemically active alpha-MoO3. The results pronounce that the MoO3/AC nanocomposites possess an aptitude as a superb bifunctional OER/HER electrocatalyst for high-performance water electrolysis.