Effective sulfur-doping in carbon by high-temperature molten salt bath and its electrocatalysis for oxygen reduction reaction

A facile high-temperature molten salt bath method was developed to effectively dope sulfur into carbon. Molten potassium sulfide acts as a high-concentration sulfur source and provides an immersion bath, thus favoring sulfur doping. Resultant sulfur-doped carbon shows an exceptionally high sulfur content of 1.50 at.%, manifesting its favorable effect on catalysing the oxygen reduction reaction.