Ru single atoms and nanoparticles immobilized on hierarchically porous carbon for robust dual-pH hydrogen evolution

Ensuring Ruthenium-based (Ru) catalysts with high metal utilization is a potential and challenging strategy for designing and constructing high catalytic activity electrocatalysts for hydrogen evolution reaction (HER). Herein, Ruthenium single atoms (SA) and Ruthenium nanoparticles (NPs) are simultaneously anchored on hierarchically porous carbon via the self-templates method for the first time. Benefiting from the synergetic effect of hierarchically porous carbon and the coexistence of Ru SA and Ru NPs, the Ru/C-800 shows attractive HER catalytic activity in acidic and alkaline solutions, with low overpotentials to drive the current density of 10 mA cm^-2 and the smallest Tafel slope. Density functional theory (DFT) results reveal that the coexistence of Ru SA and Ru NPs can positively affect charge distribution and charge transfer kinetics, and reduce the hydrogen adsorption and water dissociation free energy. This work provides a novel self-templating strategy for synthesizing high catalytic activity catalysts in a wide pH range.