Modulating Oxygen Reduction Activity in Chalcogenophene‐Incorporated Organic Electrocatalysts through Main‐Group Element Engineering

Abstract Organic small molecules (OSMs) with well‐defined structures are crucial integral components of cathode catalysts for fuel cells. Despite the acknowledged potential of heteroatom doping to enhance the catalytic performance of metal‐free carbon‐based catalysts, there exists a notable gap in conducting molecular structure and catalytic activity, particularly under the premise of maintaining a constant molecular skeleton and with a clear molecular structure. Herein, the charge distribution is modulated by introducing different chalcogens into the same molecular skeleton through main‐group engineering. Among these OSMs, the Se‐containing small molecule OSM‐Se combined with carbonized calcium alginate exhibits a notable quasi‐four‐electron‐transfer oxygen reduction reaction pathway, displaying a superior half‐wave potential (E_1/2) of 0.73 V, accompanied by outstanding electrochemical stability. Density functional theory calculations demonstrate that Se‐containing small molecules can enhance the capabilities of catalysts in adsorbing and dissociating oxygen molecules, and contribute to reducing the reaction barrier of the oxygen reduction reaction. This study presents a straightforward yet highly effective approach for metal‐free carbon‐based OSM electrocatalysts.