Surface reconstruction of NiFe layered double hydroxides by S2- corrosion for efficient oxygen evolution

Abstract

Nickel-iron layered double hydroxides (NiFe LDH) are subject to surface reconstruction by the applied anodic potential in alkaline media, and the reconstructed metal hydroxyl oxides are often considered to be the actual active material for oxygen evolution reaction (OER), so how to facilitate surface reconstruction is crucial for their performance. In this paper, the surface reconstruction of NiFe LDH nanosheets was successfully induced by S2- corrosion using rapid wet chemical engineering without affecting their crystal structure and nanomorphology; Notably, the NiOOH species formed on the corroded S-NiFe LDH/NF surface participate in the OER process as active species. The electrochemical measurements show that S-NiFe LDH/NF has a low overpotential of 250 mV and a Tafel slope of 26.3 mV dec -1 at 50 mA cm−2. This work provides a simple activation strategy for the surface reconstruction of NiFe LDH, which is an important reference for the design of advanced catalysts.