Silk‐Derived 2D Porous Carbon Nanosheets with Atomically‐Dispersed Fe‐N_x‐C Sites for Highly Efficient Oxygen Reaction Catalysts

Abstract

Abstract Controlled synthesis of highly efficient, stable, and cost‐effective oxygen reaction electrocatalysts with atomically‐dispersed Me–N x –C active sites through an effective strategy is highly desired for high‐performance energy devices. Herein, based on regenerated silk fibroin dissolved in ferric chloride and zinc chloride aqueous solution, 2D porous carbon nanosheets with atomically‐dispersed Fe–N x –C active sites and very large specific surface area (≈2105 m 2 g −1 ) are prepared through a simple thermal treatment process. Owing to the 2D porous structure with large surface area and atomic dispersion of Fe–N x –C active sites, the as‐prepared silk‐derived carbon nanosheets show superior electrochemical activity toward the oxygen reduction reaction with a half‐wave potential ( E 1/2 ) of 0.853 V, remarkable stability with only 11 mV loss in E 1/2 after 30 000 cycles, as well as good catalytic activity toward the oxygen evolution reaction. This work provides a practical and effective approach for the synthesis of high‐performance oxygen reaction catalysts towards advanced energy materials.