CoN 4 active sites coupled with low‐loading Pt as advanced oxygen electrocatalyst for proton exchange membrane fuel cells

Abstract Proton exchange membrane fuel cells (PEMFCs) are regarded as a cornerstone of next‐generation energy conversion technologies due to zero emission and high energy efficiency. However, the high cost and scarcity of conventional Pt‐based electrocatalysts hinder its commercialization. Herein, we successfully developed a platinum and cobalt bimetallic covalent organic polymer (Pt‐CoNC) electrocatalyst with low Pt loading (0.96 wt%) for the oxygen reduction reaction (ORR) by integrating Pt sites with carbon materials featuring Co‐N 4 active centers. This unique structural design not only effectively mitigates the high cost associated with Pt‐based catalysts but also notably boosts the activity and stability of non‐precious metal catalysts. The results verified that the half‐wave potential of Pt‐CoNC in the acidic ORR was increased by 105 mV as compared with pure cobalt phthalocyanine‐based covalent organic polymer (COP‐Co). Furthermore, the as‐assembled PEMFC device achieved a peak power density of 1.14 W cm −2 under an H 2 ‐O 2 atmosphere, which is comparable to commercialized 20% Pt/C catalysts.