Nanoarchitecture of 2D materials: Unveiling the power trio-Ni, Co, and GNF-in eco-friendly air breathing zinc air battery through layered double hydroxides

Abstract

Zinc-air batteries emerge as sustainable and efficient energy storage device towing to its potential for high energy density and environmental friendliness. Layered double hydroxide (LDH) specifically, exhibit unique properties like high surface area, stability and ion-exchange capacity, making them attractive for various applications. In this work, a simple and scalable one-pot urea hydrolysis process is adopted to synthesize NiCo-LDH supported on graphene nanofiber (GNF) sheets as a good substitute as a non-precious bifunctional catalyst. Ammonium fluoride as a structural-mediating agent is employed which offers a unique homogeneous 3D micro-sized hierarchical petal-like morphology of NiCo-OH. Electrochemical analysis shows low over potential with high durable around 15,000 potential cycles in a 0.5 M KOH solution which confirms the structural integrity and superior activity of NiCo-LDH/GNF catalyst in oxygen reduction and evolution reactions. The resulting NiCo-LDH/GNF composites demonstrate outstanding specific capacitance of 806 mAh g−1 with stable cycling performance up to 950 cycles and rate capability, making it promising alternative bifunctional electro catalyst in Zinc-air batteries.