Nonprecious Bimetallic (Fe,Mo)–N/C Catalyst for Efficient Oxygen Reduction Reaction
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- 作者：Ling Lin ; Zheng Kun Yang ; Yi-Fan Jiang ; An-Wu Xu
- 刊名：ACS Catalysis
- 出版年：2016
- 出版时间：July 1, 2016
- 年：2016
- 卷：6
- 期：7
- 页码：4449-4454
- 全文大小：397K
- 年卷期：0
- ISSN：2155-5435
文摘
Developing highly efficient catalysts for cathodes remains an important matter of the research of fuel cells. Here, we report a bimetallic iron- and molybdenum-based nitrogen-doped carbon catalyst ((Fe,Mo)–N/C), acting as an efficient catalyst for oxygen reduction reaction (ORR) at the cathode. The catalyst was synthesized by pyrolysis of a complex precursor obtained through a facile ion-exchange process based on the hard–soft-acid–base (HSAB) principle. The dilution effect of Mo prevents Fe species from aggregation, leading to a high content of Fe. Besides, the synergistic catalysis effect of Fe and Mo enhances the graphitization degree of carbon, resulting in a high electrical conductivity of carbon at a relative low pyrolysis temperature (700 °C). Different initial Fe/Mo mole ratios were tested to determine the optimal catalyst. The (Fe,Mo)–N/C catalyst with Fe/Mo = 0.75 affords an excellent ORR activity, comparable to commercial Pt/C catalysts, and follows a four-electron mechanism under acidic conditions. Our present work demonstrates that both Fe–Nx and Mo–Nx can act as the active sites simultaneously. Notably, we have developed a versatile, new route toward the preparation of efficient catalysts with hierarchical porous structures for fuel cells.