Fully π-conjugated dense topological salphen organic frameworks with atomic dispersed tetradentate cobalt sites for high‐efficiency electrocatalytic oxygen reduction

Abstract

Highly effective electrocatalysts are of vital importance for advanced applications. Here we show that fully π-conjugated dense topological salophen organic frameworks with atomic dispersed tetradentate cobalt sites in-situ growth on Kejtenblack are high-efficiency and durable electrocatalyst for the oxygen reduction, with a remarkable half-wave potential of 0.959 V which surpassing that of benchmark Pt/C catalyst, and is among the highest of reported single atom electrocatalysts. The electron transfer number was 3.92–3.99 and the yield of peroxide remains below 4% in 0.40–0.95 V. When employed as a cathode electrocatalyst for zinc-air batteries, it showed a high open-circuit voltage (1.5558 V) and maximum power density (178 mWcm−2) and high specific capacity (804 mAhgzn−1). The work reported here revealed that tailoring the active centers, conjugated structures, building blocks and topologies at atomic level could synergistically enhance the ORR activity which are highly valuable for zinc–air batteries and fuel cells.