Construction of schiff base-structured cobalt coordination polymers on Fe-N-C surfaces for high-efficiency ORR catalysts

The preparation of highly efficient, stable, and cost-effective catalysts to address the complex oxygen reduction reaction (ORR) in zinc-air batteries remains a significant challenge. Herein, a surface modification strategy is employed to uniformly encapsulate an Fe-N-C matrix with cobalt-coordinated conjugated organic polymers containing Schiff base structures, successfully yielding a highly active CB(cobalt-coordinated Schiff-base polymer)@Fe-N-C composite catalyst with coexisting cobalt coordination polymers and iron-nitrogen-carbon structures. In alkaline electrolytes, the CB@Fe-N-C catalyst exhibits outstanding catalytic activity (E 1/2  = 0.93 V) and stability, which are attributed to its highly conductive, structurally stable composite architecture with abundant active sites. In a zinc-air battery (ZAB), CB@Fe-N-C exhibits remarkable power density, surpassing the Pt/C benchmark. This work offers an effective synthetic strategy for preparing electrocatalysts with excellent ORR performance in zinc-air batteries.