Article Title
Highly efficient K-Fe/C catalysts derived from metal-organic frameworks towards ammonia synthesis
Authors
Pengqi Yan, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Wenhan Guo, Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 10087, China
Zibin Liang, Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 10087, China
Wei Meng, Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 10087, China
Zhen Yin, State Key Laboratory of Separation Membranes and Membrane Processes, School of Chemistry and Chemical Engineering, Tianjin Polytechnic University, Tianjin 300387, China
Siwei Li, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Mengzhu Li, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Mengtao Zhang, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Jie Yan, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Dequan Xiao, Department of Chemistry and Chemical Engineering, University of New Haven, West Haven, CT 06516, USA
Ruqiang Zou, Beijing Key Laboratory for Theory and Technology of Advanced Battery Materials, Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 10087, China
Ding Ma, Beijing National Laboratory for Molecular Sciences, College of Chemistry and Molecular Engineering and College of Engineering, and BIC-ESAT, Peking University, Beijing 100871, China
Keywords
metal-organic frameworks, pyrolysis, ammonia synthesis, iron nanoparticles, K promotion
Abstract
Fe-based catalysts have been discovered as the best elementary metal-based heterogeneous catalysts for the ammonia synthesis in industrial application during the last century. Herein, a novel and scalable strategy is developed to prepare the K-promoted Fe/C catalyst with extremely high Fe loading (> 50 wt.%) through pyrolysis of the Fe-based metal-organic framework (MOF) xerogel. The obtained K-Fe/C catalysts exhibited superior activity and stability towards ammonia synthesis. The weight-specific reaction rate of Fe/C with K2O as promoter can achieve 12.4 mmol·g−1·h−1 at 350 °C and 30.4 mmol·g−1·h−1 at 400 °C, approximately four and two times higher than that of the commercial fused-iron catalyst (3.4 mmol·g−1·h−1 at 350 °C and 16.7 mmol·g−1·h−1 at 400 °C) under the same condition, respectively. The excellent performance of K-Fe/C can be ascribed to the inherited structure derived from the metal-organic frame precursors and the promotion of potassium, which can modify the binding energy of reactant molecules on the Fe surface, transfer electrons to iron for effective activation of nitrogen, prevent agglomeration of Fe nanoparticle (NPs) and restrain side reaction of carbon matrix to methane.
Graphical Abstract
Publisher
Tsinghua University Press
Recommended Citation
Pengqi Yan,Wenhan Guo,Zibin Liang,Wei Meng,Zhen Yin,Siwei Li,Mengzhu Li,Mengtao Zhang,Jie Yan,Dequan Xiao,Ruqiang Zou,Ding Ma, Highly efficient K-Fe/C catalysts derived from metal-organic frameworks towards ammonia synthesis. NanoRes.2019, 12(9): 2341–2347
