Affiliation:
1. State Key Laboratory of Organic‐Inorganic Composites Beijing University of Chemical Technology Beijing 100029 China
2. Qingdao International Academician Park Research Institute Qingdao 266000 China
3. School of Chemical Engineering The University of New South Wales Sydney NSW 2052 Australia
Abstract
AbstractThe seawater electrolysis to produce hydrogen is a significant topic on alleviating the energy crisis. Here, the Fe, Nb‐Ni3S2 catalyst is prepared by metal‐doping strategy, and it shows high oxygen evolution reaction (OER) activity in alkaline medium, and only needs 1.491 V to deliver a current density of 100 mA cm−2 in simulated seawater. Using Fe, Nb‐Ni3S2 as a bifunctional catalyst, the two‐electrode electrolyzer only requires a voltage of 1.751 V (without impedance compensation) to drive the current density of 50 mA cm−2, and can run over 150 h stably in the simulated seawater. Importantly, In situ Raman test demonstrates that the outstanding performance of Fe, Nb‐Ni3S2 in simulated seawater is ascribed to the in situ formed sulfate protective layer induced by Nb doping, which can effectively inhibit the corrosion of chloride ion, while the protective layer is absent for Fe‐Ni3S2. The stable operation of simulated seawater electrolysis under industrial current density further confirms the stability improvement mechanism of forming protective layer. In short, this study provides a new strategy of using Nb dopants inducing the formation of protective layer to enhance the stability of seawater electrolysis.