Enhanced electrocatalytic activity by NiCu-LDH/CoS as dual co-catalysts on g-C3N4 nanosheets in NiCu-LDH@CoS/g-C3N4 nanostructure for oxygen evolution reactions

Abstract

The development of highly efficient electrocatalysts is crucial for realizing efficient oxygen evolution reactions (OERs). Herein, a novel strongly coupled ternary electrocatalyst of NiCu-layered double hydroxide (NiCu-LDH) on cobalt sulfide (CoS) and the material graphitic carbon nitride (g-C3N4) was synthesized. In OER tests, NiCu-LDH@CoS/g-C3N4 electrocatalyst exhibited excellent performance using 1 M KOH alkaline electrolyte. In the present study, the electrode potential was only 290 mV for a current density of 10 mA/cm2 and a Tafel slope of 75 mV/dec. The improved electrocatalytic activity was ascribed to the strong interaction and electronic coupling with efficient charge transfer at the CoS/g-C3N4 heterojunction interface and the enhanced electronic effects of NiCu-LDH at the NiCu-LDH@CoS/g-C3N4 interface. The optimized NiCu-LDH@CoS/g-C3N4 nanostructure was stable, with a 99.7% remarkable efficiency for the OER. This work presents a novel approach to maximize the efficiency through the synergetic effect of CoS and NiCu-LDH as dual co-catalysts for sustainable energy applications.