Fig. 1: Two-step pyrolysis and carbonization synthesis process of A-Fe2S1N5/SNC.

a The certain mass ratio of 2-benzimidazolethiol and melamine underwent confined pyrolysis in a flowing inert atmosphere. b The free radical reactions, polymerization processes, and thermally induced decomposition of 2-benzimidazolethiol and melamine during pyrolysis were performed to synthesize highly defective SNC nanosheets. c The SNC anchored dual Fe atoms through sulfur tethering and defect capture effects.