Tuesday, 11 October 2022
Zinc-air battery technology is gaining recognition as a promising energy storage device to be used in portable electronics and electric vehicles. Despite possessing high theoretical energy density, environmental and operational safety, and easy accessibility of zinc reservoirs, the successful commercialization of zinc-air batteries suffers due to the poor oxygen electrocatalysis kinetics at the air cathode. The kinetically inept oxygen reduction and oxygen evolution reactions at the cathode lead to a large overpotential barrier and poor charge-discharge cyclic performance of the rechargeable zinc-air battery. This work demonstrates designing a multi-principal metal bifunctional electrocatalyst that is directly deposited on conductive, porous, and flexible substrates to eliminate the necessity of polymeric binders. The flexible bifunctional oxygen electrocatalyst used for the cathode of solid-state ZAB is assembled with gel polymer electrolyte and zinc anode giving excellent charge-discharge cyclic stability and constant discharge voltage (close to 1.65 V). These multi-principal metal electrocatalysts constituting quasi-equimolar concentration, provide numerous combinations of surface functionality, multiple adsorption sites, and electronic environments thus enabling better optimization of the catalytic performance.