Flower-like S-doped-Ni 2 P mesoporous nanosheet-derived self-standing electrocatalytic electrode for boosting hydrogen evolution

Developing cost-effective, highly active, and stable electrocatalysts for boosting electrochemical hydrogen evolution reaction (HER) in alkaline media is playing a critical role to meet hydrogen industry in the future. Herein, an efficient HER electrocatalyst based on flowerlike S-doped Ni2P mesoporous nanosheets supported on nickel foam (S-Ni2P NSs/NF) was developed through an effective approach. The obtained S-Ni2P NSs/NF catalyst required low overpotential of only 87.5 mV and 179.1 mV to reach current density of 10 and 50 mA cm-2, respectively. Moreover, a small Tafel slope of 62.1 mV dec-1 for S-Ni2P NSs/NF demonstrated that HER process occurred with very fast kinetics. Besides high HER activity, the synthesized S-Ni2P NSs/NF catalyst exhibited superior stability and long-term durability toward HER, which had ability to operate over 30 h without degradation in catalytic performance. The unique flower-like nanosheets structure with excellent mesoporous characteristics of S-Ni2P NSs/NF resulted in maximizing electrochemical active surface area for providing a large number of electrocatalytic active sites. In addition, S doping effect could modulate electronic structure of Ni species in Ni2P, leading to accelerating rate adsorption of reaction intermediates on the surface of catalysts toward improving HER kinetics. The results not only demonstrate S-Ni2P NSs/NF as active catalyst for HER, but also offer effective strategy for improving catalytic activity of earth-abundant transition metal-based HER catalysts.