Enhanced pH-universal hydrogen evolution reactions on the Rh/MoO₃ electrocatalysts

Developing efficient electrocatalysts for pH-universal hydrogen evolution reaction (HER) is particularly appealing due to the growing demands of clean and renewable energy. Herein, a facile electrodeposition method to construct Rh nanoclusters supported by molybdenum trioxide micro sheets (Rh/MoO₃) was developed. The use of MoO₃ support can enhance hydrogen production due to the accelerated electron transfer by Mo. The interaction between the interface of Rh and MoO₃ modulates the hydrogen adsorption energies. The interfacial electron transfer from Rh to Mo optimizes H₂O adsorption, adjusts the d-band center, and fine-tunes the hydrogen binding energy, hence increasing the inherent hydrogen-evolving activities. Therefore, the Rh/MoO₃ catalyst shows outstanding performance with very low overpotentials of only 34, 49, and 29 mV at a current density of −10 mA cm⁻² in 1.0 M PBS, 0.5 M H₂SO₄, and 1.0 M KOH electrolytes, respectively. Our findings also help to create effective catalysts for pH-universal HER by leveraging particle-support interactions.