Carbon-nitrogen/graphene composite as metal-free electrocatalyst for the oxygen reduction reaction

• 来源期刊: 科学通报(英文版)
• 学科: 工学
• 年，卷（期）: 2011,（33）
• 页码范围: 3583-3589
• 页数: 7页
• 分类号: TM911.46
• 语种: 中文

摘要

Sheet-like carbon-nitrogen (CNx)/graphene composites with a high content of nitrogen (x≤0.15) was prepared by the carbonization of polypyrrole (PPy)/reduced-graphene-oxide (rGO) composite at 600-800°C. We used rGO instead of graphene oxide (GO) sheets as a template and a substrate to immobilize PPy since the PPy/GO composite agglomerates easily because of the dehydration of excess oxygen-containing groups on the GO sheets during the drying process. The dried PPy/rGO intermediate and its derived CNx/graphene products retain their high dispersion and loose-powder features. The as-prepared CNx/graphene composites have a total nitrogen content of about 10 at% and their nitrogen state is mainly of pyridinic and graphitic type. CNx/graphene composites exhibit excellent performance for the oxygen reduction reaction (ORR) in terms of electrocatalytic activity, stability and immunity towards methanol crossover and CO poisoning, suggesting their potential as metal-free electrocatalysts for the ORR.