title: Optimized electrospinning synthesis of iron-nitrogen-carbon nanofibers for high electrocatalysis of oxygen reduction in alkaline medium.
abstract: To achieve iron-nitrogen-carbon (Fe-N-C) nanofibers with excellent electrocatalysis for replacing high-cost Pt-based catalysts in the cathodes of fuel cells and metal-air batteries, we have investigated and evaluated the effects of polyacrylonitrile (PAN) concentration and the proportion of iron to PAN, along with voltage and flow rate during the electrospinning process, and thus proposed three criteria to optimize these parameters for ideal nanofiber catalysts. The best half-wave potential of an optimized catalysts is 0.82 V versus reversible hydrogen electrode in an alkaline medium, which reaches the best range of the non-precious-metal catalysts reported and is very close to that of commercial Pt/C catalysts. Furthermore, the electron-transfer number of our catalysts is superior to that of the Pt/C, indicating the catalysts undergo a four-electron process. The durability of the optimized Fe-N-C nanofibers is also better than that of the Pt/C, which is attributed to the homogeneous distribution of the active sites in our catalysts.
authors: National Center for Electron Microscopy in Beijing, Key Laboratory of Advanced Materials (MOE) and The State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084, People's Republic of China.
authors: Xingxu
authors: X
authors: Yan
authors: Kexi
authors: K
authors: Liu
authors: Xiangqing
authors: X
authors: Wang
authors: Tuo
authors: T
authors: Wang
authors: Jun
authors: J
authors: Luo
authors: Jing
authors: J
authors: Zhu