Sulfur, Nitrogen and Fluorine Triple‐Doped Metal‐Free Carbon Electrocatalysts for the Oxygen Reduction Reaction

Abstract

Abstract Currently, the development of low‐cost catalysts for replacing the precious Pt‐based catalysts for the oxygen reduction reaction (ORR) used in fuel cells is one of the major challenges. The high cost, scarcity and poor durability of the Pt‐based catalysts severely hinder the practical application of fuel cells. Here, we synthesize a S, N, F triple‐doped porous carbon material as efficient metal‐free electrocatalyst for ORR by using cheap superfine polytetrafluoroethylene powder and thiourea as precursors. Results indicate that the as‐synthesized SNF‐Carbon‐1000 under optimized condition not only shows the same onset potential (0.98 V vs. RHE) and half‐wave potential (0.86 V vs. RHE) as commercial 20 % Pt/C in alkaline media, but also a better long‐term stability and higher crossover resistance. The excellent electrocatalytic activity of SNF‐Carbon‐1000 is attributed to the successful doping of heteroatoms of S, N, and F into the carbon matrix and their synergetic effects in charge redistribution caused by N, F‐doping and the polarizability of C−S caused by S‐doping. This work provides a new approach for the synthesis of S, N, and F triple‐doped porous carbons as highly efficient metal‐free electrocatalyst for ORR.