Facile synthesis of Ru atom clusters on MXene nanosheets through gamma-ray radiation for plasma boosting hydrogen evolution reaction

Abstract

Water electrolysis with limited hydrogen yield is the main method for producing green hydrogen, which shows enhancement when coupled with solar energy. MXenes are one of the promising materials with an intensity localized surface plasmon resonance (LSPR) effect for the utilization of infrared and visible wavelengths of the solar spectrum. In this work, Ru atom clusters were anchored on Ti₃C₂T_x MXene nanosheets through gamma-ray radiation using hydrated electrons (e_aq⁻) as the reducing agent and Ti₃C₂T_x itself as the oxidizing free radical scavenger to form Ru/Ti₃C₂T_x catalysts. The as-synthesized catalysts perform enhanced activity in the hydrogen evolution reaction (HER) across all pH ranges under 808 nm near infrared (NIR) light illumination because of the plasmonic effect of Ti₃C₂T_x nanosheets. Ru/Ti₃C₂T_x with only 2.40 wt% Ru exhibits the highest HER activity under NIR light illumination with a Tafel slope of 141 mV dec⁻¹ and a current density enhancement of 3.56 mA cm⁻² at an overpotential of 200 mV. This work demonstrates the effectiveness of gamma-ray radiation for synthesizing atomically dispersed electrocatalysts with enhanced HER performance when coupled with the illumination of infrared light.