A Pentagonal Defect-Rich Metal-Free Carbon Electrocatalyst for Boosting Acidic O 2 Reduction to H 2 O 2 Production.

Metal-free carbon-based materials are considered one of the most promising two-electron oxygen reduction reaction (2e - ORR) electrocatalysts for the green synthesis of hydrogen peroxide (H 2 O 2 ). However, most reported carbon electrocatalysts perform much more effectively in alkalis than in acids. Herein, by creatively using fullerene (C 60 ) as the precursor subject to ammonia treatment, we designed and synthesized a pentagonal defect-rich nitrogen-doped carbon nanomaterial (PD/N-C). It achieves outstanding ORR activity, 2e - selectivity, and stability in acidic electrolytes, surpassing the benchmark PtHg 4 alloy catalyst. Impressively, the flow cell based on the PD/N-C catalyst achieves nearly 100% Faraday efficiency with a remarkable H 2 O 2 yield, representing the best improvement among all the metal-free catalysts. Experimental and theoretical results reveal that such superb 2e - ORR performance of PD/N-C originates from the synergism between pentagonal defects and nitrogen dopants. This work presents an effective strategy for the design and construction of highly efficient acid-resistant carbon electrocatalysts for H 2 O 2 production and beyond.