A two-dimensional heterogeneous structured Ni3Se2@MoO3 catalyst for seawater electrolysis

Hydrogen production from seawater electrolysis is quite attractive while full of challenges due to the dissatisfactory stability and low selectivity. In this work, a copper foam (CF) supported Ni3Se2@MoO3 composite (Ni3Se2@MoO3/CF) catalyst is synthesized by a facile one-step electrodeposition method. The prepared Ni3Se2@MoO3/CF catalyst demonstrates impressive activity and stability toward both the oxygen evolution reaction (OER) and hydrogen evolution reaction. The OER overpotential of Ni3Se2@MoO3/CF is 280 mV at 100 mA cm(-2), which is much lower than that of the commercial RuO2 catalyst (371 mV). In addition, the catalyst is highly selective for the OER in alkaline seawater during the anodic reaction and exhibits robust durability with almost no activity loss after the durability test for more than 200 h. The good electrocatalytic performance of the prepared catalyst should be attributed to the MoO3 particles tightly grown on the edges of Ni3Se2 nanosheets, resulting in a large specific surface area, abundant active sites, and enhanced durability.