Promoted OH <sup>−</sup> Adsorption and Cl <sup>−</sup> Repulsion Ability of Ce‐Decorated NiFe@CuO for Alkaline Seawater Electrolysis
Hongbo Zhao, Kuan Deng, Xuesong Liu, Peng Liu, Xingbin Lv, Wen Tian, Junyi Ji
Abstract
Abstract With the growing scarcity of worldwide energy and freshwater resources, utilizing abundant seawater for hydrogen production via electrolysis has become imperative. However, due to the multi‐electron intermediate process of oxygen evolution reaction (OER), and the competition reaction/erosion from Cl − , the design of highly selective and corrosion‐resistant seawater electrocatalysts remains challenging. Herein, Ce‐decorated NiFe LDH nanosheets array anchored on vertically aligned CuO nanowire (CeNiFe@CuO) is fabricated by one‐step electrodeposition strategy, where Ce doping increases the Lewis acidity and crystal imperfection degree of the composite. The CeNiFe@CuO can achieve high current density of 500 mA cm −2 with overpotential of 265 and 280 mV in KOH and alkaline natural seawater, respectively, and remain stable for 300 h at 500 mA cm −2 in alkaline seawater without apparent corrosion. Systematic experiments and mechanism analysis confirm that the excellent OER activity can be attributed to the introduction of Ce species, which bring massive oxygen vacancies and accelerate the Ni component oxidation rate. Moreover, the CeNiFe@CuO exhibits enhanced surface OH − adsorption kinetics and capacity, resulting in electrostatic exclusion of Cl − to achieve high OER stability and selectivity. This study provides new insights into the development of efficient corrosion‐resistant electrocatalysts for high‐current seawater electrolysis.