Wen-Jie Jiang, Jin-Song Hu, Xing Zhang, Yan Jiang, Bin-Bin Yu, Zi-Dong Wei and Li-Jun Wan
J. Mater. Chem. A, 2014, 2, 10154-10160, DOI: 10.1039/C4TA01780C
http://pubs.rsc.org/en/content/articlelanding/2014/ta/c4ta01780c#!divAbstract
Abstract (click image for pdf file)
The great challenge of designing nitrogen-doped carbon catalysts for oxygen reduction reaction (ORR) is how to reach high nitrogen content and further high electrocatalytic performance. By considering the requirements for high nitrogen content, proper nitrogen bonding state, and sufficient electron and mass transportation, this work developed a new nitrogen-doped carbon nanomaterial with nanoporous coaxial nanocable structure as an efficient metal-free ORR catalysts. The high nitrogen content was achieved by in-situ nitrogen-doping during the formation of nanopores. The nanoporous sheaths allowed more catalytic sites and easy accessibility of oxygen and electrolyte for fast mass transfer while carbon nanotube cores provided a three-dimensional conductive network and guaranteed fast electron transfer. As a result, the designed low-cost catalyst exhibited the excellent electrocatalytic performance as one of most active metal-free ORR catalysts.