氮掺杂石墨烯@碳纳米纤维的原位制备及其电催化氧还原性能

结合静电纺丝和热处理技术, 在含钴碳纳米纤维上原位生长了氮掺杂石墨烯, 制备了三维互通纤维网结构。研究了钴含量对产物氧还原活性的影响。结果表明: 氮掺杂石墨烯的生成和钴的引入均显著提高了电催化活性。纺丝液中六水合硝酸钴与聚丙烯腈的质量比为1: 10时, 获得的催化剂活性最优, 起始电势为0.84 V(vs RHE), 反应为近四电子路径, 具有比铂碳更好的稳定性和耐甲醇毒化能力。三维互通结构促进了电子和质子传输, 并能提供更多的活性位点, 提高电催化活性。这种方法也可用于设计其它三维互通的纤维复合物, 在能源与环境领域具有更广泛的应用前景。

In-situ Preparation and Electrocatalytic Oxygen Reduction Performance of N-doped Graphene@CNF

By combining the techniques of electrospinning and heat-treatment, N-doped graphene (NG) were in situ grown on cobalt-containing electronspun carbon nanofibers (CNF) to form three-dimensional (3D) interconnected fiber network structure. The effect of cobalt (Co) content on the oxygen reduction reaction (ORR) activity of the as-prepared samples was studied. It is demonstrated that both the formation of NG and introduction of Co significantly increase the electrocatalytic activity. The hybrid shows optimized ORR performance when the weight ratio of Co(NO₃)₂·6H₂O to PAN in electronspun solution is 1: 10. The as-obtained catalyst exhibits superior ORR catalytic performance with onset potential of 0.84 V (vs RHE), near four electron transfer pathway. In addition, the sample presents better stability and methanol tolerance than Pt/C in alkaline media. As-obtained interconnected fiber networks facilitate electron and mass transfer to provide more active sites, favorable to the enhancement of electrocatalytic activity. This strategy is also available to prepare other 3D interconnected fiber composites for using in energy and environmental fields.