Synthesis of functional Ni2P/CC catalyst and the robust performances in hydrogen evolution reaction and nitrate reduction

Abstract

The non-precious transition metal phosphides (TMPs) as robust and effective hydrogen evolution reaction (HER) catalysts have attracted enormous attention, due to the merits of earth-abundance, low price, desirable stability and high efficiency. However, the conventional preparation process of this kind of catalyst is inconvenient. Herein, we report a facile approach toward the fabrication of nickel phosphide (Ni2P) assembled on carbon cloth (CC) via the coupling method of electroless plating and low temperature phosphorization. Then, the crystallinity, morphology and chemical component of fabricated self-supporting Ni2P/CC catalyst employed for the HER process were characterized, and the HER property was successively evaluated in three types of electrolytes (i.e., acidic, neutral and alkaline solutions). The as-prepared Ni2P/CC catalyst displays a remarkable HER performance, which can be corroborated by the small Tafel slope (b = 50 mV dec−1), high exchange current density (j0 = 6.6 × 10−2 mA cm−2), acceptable overpotential (119 mV) to attain the current density of 10 mA cm−2, as well as the superb stability (<5% decay after 24 h potentiostatic test) in 0.5 M H2SO4. In addition, it should be noted that the HER process of Ni2P/CC catalyst can be competent for the reduction of nitrate from the solution, and an efficiency of 63.2% for this nutrient pollutant is achieved.