P-Doped Boosting the Activity of Ni-Mo Nanocatalysts for Efficient Alkaline Water Electrolysis of Hydrogen Evolution.

Decarbonization of transportation sector is critical to achieve net-zero emissions economy by 2060. It is of importance to develop highly efficient electrocatalysts for decarbonization. Ni-Mo-P ternary alloy catalysts were electrodeposited on Cu foam (CF), and the rough surface of Ni-Mo-P/CF catalysts was composed of uniformly dense small clusters with the size of 200 nm. The catalyst was composed of a mixture of nanocrystals and amorphous, with metallic Ni and its solid solution, Ni and Mo oxides, and Ni(OH)2. The Ni70.2Mo27.0P2.8/CF catalyst exhibited Tafel slope of 63.1 mV·dec−1 in alkaline medium, and delivered a current density of 10 mA·cm−2 at an overpotential of 68 mV, demonstrating the excellent hydrogen evolution reaction (HER) activity due to the large active surface area, the synergistic effect and high electrical conductivity of the electrode. After 1000 cycles testing, Ni70.2Mo27.0P2.8/CF catalyst showed an increase of 2.8 mV in hydrogen evolution overpotential and almost no voltage decay was present in chronopotentiometric test for 10 h. The good HER performance of Ni-Mo-P/CF catalysts had a significant potential to be utilized in commercial water electrolyzer.Graphical Abstract: Decarbonization of transportation sector is critical to achieve net-zero emissions economy by 2060. It is of importance to develop highly efficient electrocatalysts for decarbonization. Ni-Mo-P ternary alloy catalysts were electrodeposited on Cu foam (CF), and the rough surface of Ni-Mo-P/CF catalysts was composed of uniformly dense small clusters with the size of 200 nm. The catalyst was composed of a mixture of nanocrystals and amorphous, with metallic Ni and its solid solution, Ni and Mo oxides, and Ni(OH)2. The Ni70.2Mo27.0P2.8/CF catalyst exhibited Tafel slope of 63.1 mV·dec−1 in alkaline medium, and delivered a current density of 10 mA·cm−2 at an overpotential of 68 mV, demonstrating the excellent hydrogen evolution reaction (HER) activity due to the large active surface area, the synergistic effect and high electrical conductivity of the electrode. After 1000 cycles testing, Ni70.2Mo27.0P2.8/CF catalyst showed an increase of 2.8 mV in hydrogen evolution overpotential and almost no voltage decay was present in chronopotentiometric test for 10 h. The good HER performance of Ni-Mo-P/CF catalysts had a significant potential to be utilized in commercial water electrolyzer. [ABSTRACT FROM AUTHOR]