Microstrain Engineered NixS2/PtNi Porous Nanowires for Boosting Hydrogen Evolution Activity

The rational design and fabrication of Pt-based electrocatalysts with multiple active sites for hydrogen evolution reaction (HER) are urgently needed for water splitting. Herein, through microstrain engineering, one-dimensional porous nanowires (NWs) with tailored NixS2/PtNi heterostructures have been prepared by the sulfurization of PtNi NWs. The catalyst exhibited superb HER electrocatalytic activity in both alkaline and acid media. The overpotentials of the optimal catalyst NiS2/PtNi at 10 mA cm(-2) for HER are as low as 14 and 15 mV in 0.1 M KOH and 0.1 M HClO4, respectively, much lower than those of a state-of-the-art commercial Pt/C catalyst. The NixS2/PtNi heterostructures with tailored electronic structure and abundant microstrains play as the HER active sites. In addition, the synergistic effect between the Ni3S2 or NiS2 and PtNi contributes the boosted HER performance in either alkaline medium. This work provides an effective method for developing Pt-based HER catalysts by microstrain engineered heterostructures.

Automated summary

The study successfully prepared one-dimensional porous nanowires with tailored NixS2/PtNi heterostructures through microstrain engineering, displaying superb HER electrocatalytic activity. The NiS2/PtNi catalyst showed significantly lower overpotentials for HER in both alkaline and acid media compared to a state-of-the-art commercial Pt/C catalyst. The engineered heterostructures with tailored electronic structure and abundant microstrains serve as active sites for HER, contributing to the boosted performance.