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Direct conversion of methane with O2 at room temperature over edge-rich MoS2

Nature Catalysis volume 6, pages 1052–1061 (2023)Cite this article

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Abstract

Conversion of methane to value-added chemicals at low temperature by directly using inexpensive O2 as oxidant offers an ideal route for methane utilization but remains a great challenge due to the chemical inertness of methane and the low activity of O2. Methane monooxygenase is the only known natural catalyst that can convert methane with O2 at room temperature. Here we report the realization of an artificial process for the direct methane conversion to C1 oxygenates with O2 on an edge-rich MoS2 catalyst at 25 °C, which delivers a remarkable methane conversion of 4.2% with >99% selectivity for C1 oxygenates. In situ spectroscopic and microscopic characterizations and theoretical calculations reveal that the binuclear molybdenum sites of sulfur vacancies at the MoS2 edge can directly dissociate O2 to form O=Mo=O* active species, which can activate the C–H bond and enable methane conversion at room temperature.

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Fig. 1: Room-temperature CH4 conversion by O2 over the MoS2 and MMO catalysts.
Fig. 2: Investigation of the catalytic performance of the MoS2 catalysts in CH4 conversion with O2.
Fig. 3: Quantitative analysis of active sites of the MoS2 catalysts for CH4 conversion with O2.
Fig. 4: Investigation of the active sites and reaction mechanism for CH4 conversion.
Fig. 5: DFT studies of the reaction mechanisms of CH4 conversion with O2 at the MoS2 edge.

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All data supporting this work are available in the article and its Supplementary Information or are available from the corresponding authors upon request. Source data are provided with this paper.

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Acknowledgements

This work received financial support from the National Key R&D Program of China (2022YFA1504500 to D.D. and 2022YFA1503100 to X.C.), the National Natural Science Foundation of China (21988101, 21890753, 22225204 to D.D., 92145301 to L.Y. and 22272174 to X.C.), the Strategic Priority Research Program of the Chinese Academy of Science (XDB36030200 to D.D.), the Fundamental Research Funds for the Central Universities (20720220008 to D.D.) and the CAS Project for Young Scientists in Basic Research (YSBR-028 to X.C.). We thank the staff at XAFS beamline (BL14W1) and D-Line (BL05U) of the Shanghai Synchrotron Radiation Facilities for assistance with the EXAFS, XANES and ED-XAS measurements.

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  1. These authors contributed equally: Jun Mao, Huan Liu, Xiaoju Cui.

Authors and Affiliations

  1. State Key Laboratory of Physical Chemistry of Solid Surfaces, Collaborative Innovation Center of Chemistry for Energy Materials, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, China

    Jun Mao, Yanping Zheng, Mingshu Chen, Yanan Li, Guilan Xu & Dehui Deng

  2. State Key Laboratory of Catalysis, Collaborative Innovation Center of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, China

    Jun Mao, Huan Liu, Xiaoju Cui, Yunlong Zhang, Xiangyu Meng, Zhenchao Zhao, Guangjin Hou, Jingting Hu, Rui Huang, Liang Yu & Dehui Deng

  3. University of Chinese Academy of Sciences, Beijing, China

    Xiaoju Cui, Yunlong Zhang, Xiangyu Meng, Zhenchao Zhao, Guangjin Hou, Liang Yu & Dehui Deng

  4. National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, China

    Yang Pan

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Contributions

D.D. conceived and designed the experiments. J.M. undertook the materials synthesis, characterization and performance testing. H.L., X.M. and L.Y. contributed to the DFT calculations. Y. Zhang performed the HAADF-STEM. Y. Zheng and M.C. assisted with the XPS. Y.P. assisted with the in situ synchrotron-based vacuum ultraviolet photoionization mass spectrometry test. X.C., Z.Z. and G.H. assisted with the NMR. J.H., Y.L., G.X. and R.H. assisted with data analysis and paper revision. J.M., H.L., X.C., L.Y. and D.D. co-wrote the paper. All the authors discussed and revised the paper.

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Correspondence to Liang Yu or Dehui Deng.

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Atomic coordinates of the optimized computational models.

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Mao, J., Liu, H., Cui, X. et al. Direct conversion of methane with O2 at room temperature over edge-rich MoS2. Nat Catal 6, 1052–1061 (2023). https://doi.org/10.1038/s41929-023-01030-2

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