Single Atom Ru Doped Ni2P/Fe3P Heterostructure for Boosting Hydrogen Evolution for Water Splitting

Abstract Modulating the chemical composition and structure has been considered as one of the most promising strategies for developing high‐efficient water splitting catalysts. Here, a single‐atom Ru doped Ni 2 P/Fe 3 P catalyst is synthesized by introducing the dispersed Ru atoms to adjust Ni 2 P/Fe 3 P heterostructure. Single atom Ru provides effective hydrogen evolution reaction (HER) active sites for boosting catalytic activities. The catalyst with only 0.2 wt.% content of Ru exhibits an overpotential of 19.3 mV at 10 mA cm −2 , which is obviously lower than 146.1 mV of Ni 2 P/Fe 3 P. Notably, an alkaline overall water electrolyzer based on Ru‐Ni 2 P/Fe 3 P catalysts achieves a cell voltage of 1.47 V and operates over 600 h at 10 mA cm −2 , which is superior to that of benchmark RuO 2 //Pt/C (1.61 V). The theoretical calculations further confirm that Ru single atom doping can effectively optimize the hydrogen/water adsorption free energy of the active site and therefore improve the HER activity of heterostructure. This work provides a valuable reference to design high‐activity and durability catalyst for water splitting through the double modulation of interface‐effect and atomic doping.