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

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 α-MoO₃. The results pronounce that the MoO₃/AC nanocomposites possess an aptitude as a superb bifunctional OER/HER electrocatalyst for high-performance water electrolysis.