Construction of Quench-Induced Ru-Doped CoNiP Hierarchical Spheres for Hydrogen Evolution at High Current Densities.

Optimizing the electronic configuration improved the electrocatalytic performance of Ru doping. However, efficiently doping Ru and ensuring its stability in the hollow hierarchical structure posed a challenge. This work innovatively utilized the huge temperature difference between calcination and ice water (0 °C) to rapidly dope Ru atoms onto the CoNiP hierarchical spheres. Notably, the Ru-anchored hierarchical spheres enhanced the active area and internal space utilization. In addition, the addition of Ru dopant optimized the electronic structure and hydrogen evolution reaction (HER) kinetics of CoNiP. Surprisingly, Ru-CoNiP only required 250 mV to generate 1 A cm^-2, which was 1.5 times that of commercial Pt/C. Moreover, its activation energy (E_a) was 24.3% lower than CoNiP, further confirming that the Ru dopant reduced the energy barrier of alkaline HER. In conclusion, this work proposed a new method for promoting the doping of trace amounts of ruthenium into hierarchical spheres through quenching.