Dual‐Functional NaCl Template Strategy towards Synthesis of Metal‐Free Sulfur/nitrogen co‐Doped Carbon Nanosheets Catalysts for Oxygen Reduction Reaction

Developing eco‐friendly, high‐efficiency and cost‐effective catalysts for oxygen reduction reaction are significantly crucial for the application of direct‐methanol fuel cells. The metal‐free sulfur/nitrogen in‐situ co‐doped carbon nanosheets are prepared through polymerization process and carbonization process using aniline as a nitrogen source, 4‐aminobenzenesulfonamide as a sulfur source and NaCl as a template and protective layer. The obtained catalysts show the obvious two dimensional nanosheet structure with successful doping of S and N. Benefiting from high contents of S atoms and N atom, high special surface area and graphitic degree, well‐ordered micropores and synergetic interaction between thiophenic‐S, pyridinic N and graphitic N, the optimal catalyst S3/N‐CNS800 shows excellent oxygen reduction performance with 13.2 mV more positive half‐wave potential than that of 20% Pt/C, superior long‐term durability and tolerance to methanol crossover.