Plasmon-induced local electric field improved hydrogen evolution reaction on Ag/Mo₂C nanosheets

Electrocatalytic water splitting offers a promising way for hydrogen production with near-zero emissions. Carbides, such as molybdenum carbides (Mo₂C), are promising materials for hydrogen evolution reaction (HER) but still suffer from poor intrinsic water activation properties. Here, we developed a plasmon-induced local electric field (PILEF) strategy to solve this barrier. Silver (Ag) nanoparticles decorated Mo₂C nanosheets (Ag/Mo₂C) were successfully prepared by electrostatic adsorption. The visible light excited the PILEF on Ag/Mo₂C remarkably reducing the activation energy by 92.7 kJ·mol⁻¹ from 147.3 kJ·mol⁻¹ of Mo₂C to 54.6 kJ·mol⁻¹. As a result, the plasmonic Ag/Mo₂C significantly enhances ~ 2.3-fold of the current density from 2.8 mA·cm⁻² of Mo₂C to 6.5 mA·cm⁻² at −3 V vs. RHE and reduces the overpotential by 104 mV from 403 mV of dark state to 299 mV of light state at the current density of 10 mA·cm⁻², achieving better performance than reported catalysts. This research demonstrates that PILEF enhances HER activities, offering a potential strategy for boosting the intrinsic activities of catalysts.