Cobalt–nickel bimetallic hybridized nitrogen-doped hierarchical porous carbon as efficient oxygen reduction electrocatalyst

Efficient and cost-effective non-precious metal catalysts play a crucial role in the evolution of energy storage and conversion technologies. This work introduces a novel cobalt–nickel bimetallic catalyst (Co x /Ni y –N–C), synthesized via SiO 2 spheres as templates and ZIF-8 as precursors, aiming to address this critical need. The Co 1 Ni 1 –N–C catalyst, synthesized with a 1:1 Co to Ni doping ratio, displayed exceptional electrocatalytic activity for oxygen reduction. Its impressive half-wave potential of 0.81 V and limiting current density of 4.89 mA cm −2 nearly approached those of Pt/C catalysts (0.82 V and 5.09 mA cm −2 ), showcasing its competitive edge. Integration of the Co 1 Ni 1 –N–C catalyst into a zinc-air battery demonstrated substantial promise, yielding a commendable power density of 185.17 mW cm −2 , marginally trailing behind the commercial Pt/C catalyst (198.33 mW cm −2 ). By offering a cost-effective alternative without compromising efficiency, this research significantly contributes to the wider adoption of sustainable energy technologies.