Plasma-assisted highly dispersed Pt single atoms on Ru nanoclusters electrocatalyst for pH-universal hydrogen evolution

Exploring highly active and stable electrocatalyst using trace noble metals for hydrogen evolution reaction (HER) is urgently needed but still challenging. Here, atomically dispersed Pt on ultrafine Ru nanoclusters (similar to 1.46 nm) loaded by the commercial acetylene black (Acet) support is fabricated by a facile one-step cold-plasma technique. The Pt single atoms on Ru nanoclusters electrocatalyst (Pt-0.47-Ru/Acet) with 0.47 wt% content of Pt exhibit an excellent HER activity in all pH, achieving ultralow overpotential of only 17, 28, and 8 mV at 10 mA.cm(-2) in 1 M KOH, 0.5 M H2SO4, and 1 M PBS, respectively. And the mass activity of Pt-0.47-Ru/Acet catalyst in alkaline is about 5.54 and 2.15 times that of commercial Ru/C and Pt/C catalyst at an overpotential of 100 mV, respectively. Meanwhile, after 8000 CV cycles, there is barely performance decrease for Pt-0.47-Ru/Acet, displaying good stability. DFT calculation reveals that the Pt single atoms could effectively regulate the electronic structure of Ru clusters, and reduce the energy barriers of water dissociation (Volmer step) as well as subsequent hydrogen evolution (Heyrovsky step), thus enhancing the alkaline HER performance effectively. This work provides an effective approach to designing a high-performance HER electrocatalyst with the atomic-dimension Pt surface modification.