Cr-doped NiZn layered double hydroxides with surface reconstruction toward the enhanced water splitting

The search for highly efficient earth-abundant self-supported nanoelectrodes for the water-splitting process is an urgent and important task. Various methods have been employed to enhance the activity and long-term stability of the electrodes. The phenomenon of surface species reconstruction has been reported many times in the actual operation of catalysts. Herein, an efficient integrated trimetallic Cr-NiZn layered double hydroxides (LDH) electrocatalyst was systematically synthesized by one-step electrodeposition. The time- and concentration-optimized Cr-NiZn LDH catalyst for oxygen evolution reaction can achieve a current density of 50 mA cm−2 at a low overpotential of 292 mV in a 1.0 M KOH electrolyte. The high-performance was attributed to the reconstruction of surface-active substances and the formation of oxygen defects. The research shows that doping can promote the reconstruction process and increase the number of defects to a greater extent. This feasible modulation strategy can be also be applied in other energy catalysis fields.