Abstract
Hydrogen-assisted dehydrochlorination process (HaDHC) is an attractive route for the production of fluorine-containing olefins under relatively mild conditions, so far lacking the highly efficient metal-based catalysts and their design strategy. Here, we report a nano-MgF2 supported Pd-Ag catalyst with a tunable Pd dispersion, which is optimized by the Pd-Ag alloy degree in the fresh catalyst and subsequently in situ chlorination during the induction period of reaction. After the in situ restructuring process, the resulting Pd-Ag/nano-MgF2 catalysts with atomically dispersed Pd sites exhibited an excellent catalytic performance for HaDHC of 1,1,1,2-tetrafluoro-2-chloropropane (HCFC-244bb) to 2,3,3,3-tetrafluoropropene (HFO-1234yf), the new-generation refrigerant, with a conversion of ca. 60% and HFO-1234yf selectivity of ca. 82% at 270 °C. Characterization results reveal that the Pd-Ag alloy degree in the fresh catalyst can be facilely tuned by changing the impregnation sequences for bimetallic precursors during catalyst preparation due to different metal-support interactions. Constructing a high Pd-Ag alloy degree offers a high in situ chlorination degree of the catalyst surface to finally get highly isolated Pd sites. Adsorption and computational results demonstrate that the chemisorbed hydrogen species on the single atom Pd sites (Pd-F and Pd-F3 sites) boost the HFO-1234yf formation, while the spillover hydrogen species derived from the large Pd ensembles (Pd6, Pd7, and Pd8 clusters) contribute to the formation of deep hydrogeneration product, 1,1,1,2-tetrafluoropropane (HFC-254eb).
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Data availability
The data that support the findings of this study are available from the corresponding author upon request. The raw data for the theoretical calculations during this study are included in the Supplementary Data 1 file. All the raw data for the figures during this study are included in Supplementary Data 2 file.
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Acknowledgements
We are grateful to be financially supported by the Central-guided local Sci-Tech Development Fund (No. 2022ZY2-JCYJ-02), Smart Grid-National Science and Technology Major Project of China (No. 2025ZD0807500), and Basic Research Program in Natural Science of Shanxi Province (No. 2025JC-YBQN-216, 2025SYS-SYSZD-017). Erhard Kemnitz is dedicating this paper to Prof. Dr. Christian Limberg on the occasion of his 60th birthday.
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C.Y.: Investigation, Methodology, and Experiments. W.M.: Conception, Resources, Methodology, and Writing - Reviewing & Editing. Xingzong Dong: Formal analysis. S.T.: Formal analysis. J.S.: DFT calculation. Zhaotie Liu: Writing - Review & Editing and Funding acquisition. W.Z.: Writing - Review & Editing and Funding acquisition. Jian Lu: Writing - Review & Editing and Funding acquisition. E.K.: Writing - Review & Editing.
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Yang, C., Mao, W., Dong, X. et al. Hydrogen-assisted dehydrochlorination of 1,1,1,2-tetrafluoro-2-chloropropane to 2,3,3,3-tetrafluoropropene over Pd-Ag/nano-MgF2 with optimized Pd isolated sites. Commun Chem (2026). https://doi.org/10.1038/s42004-026-01896-w
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DOI: https://doi.org/10.1038/s42004-026-01896-w
