Zhang Mengtao, Zhu Yuchen, Yan Jie, Xie Junzhong, Yu Tao, Peng Mi, Zhao Jiayun, Xu Yao, Li Aowen, Jia ChunJiang, He Lin, Wang Meng, Zhou Wu, Wang Rongming, Jiang Hong, Shi Chuan, Rodriguez Jose, Ma Ding
Beijing National Laboratory for Molecular Sciences, New Cornerstone Laboratory, College of Chemistry and Molecular Engineering, Peking University, Beijing, 100871, China.
State Key Laboratory for Advanced Metals and Materials, University of Science and Technology Beijing, Beijing, 100083, China.
Angew Chem Int Ed Engl. 2025 Feb 3;64(6):e202418645. doi: 10.1002/anie.202418645. Epub 2024 Dec 16.
Molybdenum carbide has been reported as an efficient and stable catalyst for reverse water-gas shift (RWGS) reaction. The conventional understanding of the mechanism suggests domination of the surface phenomena, with only surface or subsurface layers partaking in the catalytic cycle. In this study, we presented a highly active MoC catalyst from carburization process, which showed a mass-specific reaction rate over 260 μm with dynamic carbon flux in the bulk phase of the catalyst. Through Isotopic Temperature-Programmed Reaction (ITPR) analysis and Environmental Transmission Electron Microscopy (ETEM), we discerned dynamic carbon flow circulating between the α-MoC bulk phase and the gas phase reactants under the RWGS reaction atmosphere. This circulation, essential to maintaining the structural stability of the metastable α-MoC and its ultra-high reactivity, is accompanied by thorough carbon component exchange among the bulk, the surface and the gas-phase reactants during the reaction process.
碳化钼已被报道为一种用于逆水煤气变换（RWGS）反应的高效且稳定的催化剂。对该反应机理的传统理解认为表面现象起主导作用，只有表面或次表面层参与催化循环。在本研究中，我们通过渗碳过程制备了一种高活性的碳化钼催化剂，该催化剂在催化剂体相中具有动态碳通量，其质量比反应速率超过260 μm。通过同位素程序升温反应（ITPR）分析和环境透射电子显微镜（ETEM），我们发现在RWGS反应气氛下，动态碳流在α-MoC体相与气相反应物之间循环。这种循环对于维持亚稳α-MoC的结构稳定性及其超高反应活性至关重要，并且在反应过程中伴随着体相、表面和气相反应物之间彻底的碳组分交换。
