La incorporation induced electronic structure tailoring of NiCr-layered double hydroxide for the water oxidation reaction

Abstract

The production of green hydrogen by electrolysis is the pivotal technology for the sustainable energy transition. In water electrolysis, the kinetics of the oxygen evolution reaction (OER) is regarded as slow and demands a high overpotential; hence, the development of a catalyst to facilitate OER at a lower overpotential is imperative. In this study we created electronic manipulations into the NiCr layered double hydroxide structure by the La incorporation resulting in the boosted reaction kinetics with low overpotential. The LaNiCr<inf>0.3</inf>LDH exhibits the overpotential of 361 mV to drive the current density of 500 mA cm−2. Experimental findings revealed that the reaction proceeds via lattice oxygen mechanism (LOM). The electronic modulation results in the shifting of the reaction mechanism from AEM to LOM. The catalyst also exhibits good durability at the high current density of 300 mA cm−2 for the 120 h with no significant loss in the current density. The study offers a comprehensive examination of the electronic structural modification of layered double hydroxide-based materials and their mechanistic transition from adsorbate evolution mechanism (AEM) to LOM.