Advances in the design of highly stable NiFe-LDH electrocatalysts for oxygen evolution in seawater

Direct seawater electrolysis, as a multifunctional technology, has the advantages of clean hydrogen production, desalination of seawater and utilization of multiple resources, with superb economic benefits and resource conservation. However, due to the presence of high concentration of Cl- in seawater, well-designed seawater electrocatalysts with excellent catalytic performance and high corrosion resistance are required. It is well known that NiFe-based hydroxide layered double hydroxide (NiFe-LDH) electrocatalysts have high oxygen evolution reaction (OER) activity. However, most of the current studies are based on laboratory conditions without industrial applications, and the OER efficiencies of these catalysts have yet to be verified under the extreme operating conditions of real electrolyzer. In this paper, we propose to rationally design NiFe-LDH seawater electrocatalysts from three perspectives: 1) optimizing the intrinsic activity of the catalysts, 2) constructing the protective layer, and 3) regulating the electrolyte, in order to optimize the efficiency of anodic oxidation reaction and improve its corrosion resistance. Meanwhile, combined with the design of seawater electrolyzer, it explores the cutting-edge technology of seawater electrolysis combined with electrolyzer to realize green hydrogen production, which is of some guiding significance to optimize seawater resources.