Fabrication of a 3D self-supporting Ni–P/Ni2P/CC composite and its robust hydrogen evolution reaction properties in alkaline solution†
Developing robust and low-cost hydrogen evolution reaction (HER) catalysts in alkaline media still faces enormous challenges. Herein, a novel 3D self-supporting nickel phosphorus/nickel phosphide/carbon cloth (Ni–P/Ni2P/CC) composite was fabricated by using combined processes of nickel phosphorus electrodeposition, hydrothermal synthesis and low temperature phosphorization techniques, for the loading of Ni–P nanoparticles and Ni2P nanosheets onto the surface of CC. The characteristics of the fabricated Ni–P/Ni2P/CC composite in terms of crystallinity, surface morphology and chemical components were analyzed, and the HER properties in alkaline solution were evaluated. The synthesized Ni–P/Ni2P/CC composite exhibits preeminent HER activity; among the three composites, the Ni–P/Ni2P/CC-2 sample displays the highest catalytic activity with a low overpotential of 95 mV to afford a current density of 10 mA cm−2. Moreover, this composite exhibits outstanding electrochemical stability (without apparent loss in HER activity after 2000 cyclic voltammetry cycles). For this self-supporting Ni–P/Ni2P/CC composite, the deposited Ni–P nanoparticles fill the sites not occupied by Ni2P nanosheets on the surface of CC, and thus the effect of the synergy between Ni–P and Ni2P on the enhancement in HER performance is verified. The fabricated Ni–P/Ni2P/CC composite deserves to be considered as an appealing candidate for HER application in alkaline solution.