Recent progress on layered double hydroxides-based electrocatalysts for electrochemical water splitting

Abstract

Replacing global depleting fossil fuels with sustainable energy sources that are affordable and environmentally-benign, is from the most pressing challenges for the future socio-economic developments. To that goal, electrochemical water splitting would provide green hydrogen fuel which is considered one of the most promising energy carriers. However, the viability of the process still hinges on the availability of robust earth-abundant electrocatalysts that catalyze the cathodic hydrogen evolution reaction (HER) and the anodic oxygen evolution reaction (OER). In recent years, transition metal based layered double hydroxides (LDHs) electrocatalysts, with advantageous physio-chemical properties, can represent a promising outstanding research approaches to accelerate the sluggish electrochemical kinetics of these two half-reactions. Herein, we present brief explanations of the reaction mechanisms and the important parameters relating to the electrochemical water splitting along with the recent developments of different LDHs derived electrocatalysts towards the HER/OER performances. Furthermore, the innovative fabrication strategies of the LDHs systems and the subsequent evolution of the LDHs classes, including adopted modification strategies including cation/anion doping, defect engineering, exchanging interlayer anions, nanostructured morphology, designing hierarchical heterostructures or nanocomposites, etc. Finally, the current perspectives and challenges of some critical issues as well as the future opportunities for the developments of outstanding LDHs-based electrocatalysts for electrochemical water electrolysis are also provided.