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Palladium and Ruthenium Dual-Single-Atom Sites on Porous Ionic Polymers for Acetylene Dialkoxycarbonylation: Synergetic Effects Stabilize the Active Site and Increase CO Adsorption |
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| Authors: | Xingju Li Jiaqian Wang Qiao Yuan Xiangen Song Jiali Mu Yao Wei Li Yan Fanfei Sun Siquan Feng Yutong Cai Zheng Jiang Zhongkang Han Yunjie Ding |
| Affiliation: | 1. Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023 China Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026 China These authors contributed equally to this work.;2. School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027 China These authors contributed equally to this work.;3. Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023 China University of Chinese Academy of Sciences, Beijing, 100049 China These authors contributed equally to this work.;4. Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023 China;5. Shanghai Synchrotron Radiation Facility, Shanghai Institute of Applied Physics;6. Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204 China University of Chinese Academy of Sciences, Beijing, 100049 China;7. Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204 China;8. Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023 China University of Chinese Academy of Sciences, Beijing, 100049 China;9. School of Materials Science and Engineering, Zhejiang University, Hangzhou, Zhejiang, 310027 China |
| Abstract: | Heterogeneous single-metal-site catalysts usually suffer from poor stability, thereby limiting industrial applications. Dual Pd1−Ru1 single-atom-sites supported on porous ionic polymers (Pd1−Ru1/PIPs) were constructed using a wetness impregnation method. The two isolated metal species in the form of a binuclear complex were immobilized on the cationic framework of PIPs through ionic bonds. Compared to the single Pd- or Ru-site catalyst, the dual single-atom system exhibits higher activity with 98 % acetylene conversion and near 100 % selectivity to dialkoxycarbonylation products, as well as better cycling stability for ten cycles without obvious decay. Based on DFT calculations, it was found that the single-Ru site exhibited a strong CO adsorption energy of −1.6 eV, leading to an increase in the local CO concentration of the catalyst. Notably, the Pd1−Ru1/PIPs catalyst had a much lower energy barrier of 2.49 eV compared to 3.87 eV of Pd1/PIPs for the rate-determining step. The synergetic effect between neighboring single sites Pd1 and Ru1 not only enhanced the overall activity, but also stabilized PdII active sites. The discovery of synergetic effects between single sites can deepen our understanding of single-site catalysts at the molecular level. |
| Keywords: | Alkyne Dialkoxycarbonylation Dual-Single-Atom Sites First Principles Calculations Porous Ionic Polymers |