Ar Plasma-Exfoliated Ultrathin NiCo-Layered Double Hydroxide Nanosheets for Enhanced Oxygen Evolution

Abstract

Layered double hydroxide (LDH)-based materials are frequently used for oxygen evolution reactions (OERs) due to their promising properties in overcoming the large energy barrier. In this work, the controllably synthesized NiCo-LDHs nanosheets are treated by Ar plasma and display superior activity as well as high durability for OER processes, where there is a much lower overpotential of 299 mV at 10 mA cm–2 and a smaller Tafel slope of 45 mV dec–1 as compared to the pristine material (347 mV and 149 mV dec–1, respectively). The characterization results reveal that numerous defects induced by Ar plasma on the surface of ultrathin NiCo-LDHs nanosheets, leading to many more exposed active sites, faster kinetics, and lower resistance. This work offers inspiration for the rational design of additional active and efficient LDH-based materials for OER.