Rapid synthesis of active Pt single atoms and Ru clusters on carbon black via a highly efficient microwave strategy for the hydrogen evolution reaction in acidic and alkaline media

Abstract

Loaded single-atom catalysts (SACs) exhibit high potential for electrocatalytic hydrogen evolution reactions (HER) owing to their unsaturated coordination environments and quantum size effects. However, SACs with only one active center can limit reactions involving multiple atoms, affecting adsorption efficiency. This paper presents a synergistic catalyst, Pt₁Ru_x@C, successfully synthesized using an efficient microwave reduction strategy to load Pt₁ atoms and Ru_x clusters onto carbon black for electrocatalytic HER in just 50 seconds. Characterization and theoretical calculations show that the interaction between Pt₁ and Ru_x on the Pt₁Ru_x@C surface optimizes HER kinetics and achieves unique acid/alkaline reactivity. Pt₁Ru_x@C requires overpotentials of only 90.2 mV (acidic)/141.8 mV (alkaline) to achieve current densities of 100 mA cm⁻² (acidic)/40 mA cm⁻² (alkaline), outperforming commercial 20 wt% Pt/C. It also exhibits a low Tafel slope, high activity, and excellent stability. In conclusion, this study introduces a new path for efficient, cost-effective, and controllable electrocatalyst development.