Facile synthesis of ultrathin S-N co-doped carbon nanosheet as ORR electrocatalysts for application in sustainable zinc-air battery

The exploration of inexpensive, efficient electro-materials for oxygen reduction reactions in the field of zinc-air batteries has attracted the attention of researchers. Metal-free carbon catalysts with adulteration heteroatoms have been considered in recent years as the most promising alternative to conventional Pt-based electrocatalysts. Herein, we have researched a simple and high-performance grinding and pyrolyzing strategy for the preparation of S-N co-doped carbon nanosheets (S-N-C) with a 3D ultrathin structure that serves as resultful catalysts for ORR in zinc-air batteries. As expected, the prepared S-N-C 1000 catalysts have a super-colossal specific surface area and exhibit splendid ORR catalytic performance with half-wave potentials up to 0.858 V, which is superior to Pt/C. Furthermore, S-N-C 1000 catalysts show good stability and resistance to methanol poisoning. Additionally, the zinc-air batteries employing S-N-C 1000 as the air cathode also show excellent electrochemical performance. The power density of 164.68 mW cm−2, the cycling stability of more than 600 h at 5 mA cm−2, and the specific capacity of 830.85 mAh gZn−1 point to a possible application in zinc-air batteries. Therefore, this effective and environmentally friendly synthetic method may present a novel use for non-metallic heteroatom-doped carbon materials in zinc-air batteries.