Homolytic H2 dissociation for enhanced hydrogenation catalysis on oxides

Chengsheng Yang; Sicong Ma; Yongmei Liu; Lihua Wang; Desheng Yuan; Wei-Peng Shao; Lunjia Zhang; Fan Yang; Tiejun Lin; Hongxin Ding; Heyong He; Zhi-Pan Liu; Yong Cao; Yifeng Zhu; Xinhe Bao

doi:10.1038/s41467-024-44711-7

Homolytic H₂ dissociation for enhanced hydrogenation catalysis on oxides

Nat Commun. 2024 Jan 15;15(1):540. doi: 10.1038/s41467-024-44711-7.

Authors

Chengsheng Yang¹, Sicong Ma², Yongmei Liu¹, Lihua Wang³, Desheng Yuan¹, Wei-Peng Shao⁴, Lunjia Zhang⁴, Fan Yang⁴, Tiejun Lin⁵, Hongxin Ding¹, Heyong He¹, Zhi-Pan Liu^{1

6}, Yong Cao¹, Yifeng Zhu⁷, Xinhe Bao^{8

9}

Affiliations

¹ Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai, 200438, China.
² Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China. scma@mail.sioc.ac.cn.
³ Shanghai Synchrotron Radiation Facility, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201204, China.
⁴ School of Physical Science and Technology, Shanghai Tech University, Shanghai, 201210, China.
⁵ Key Laboratory of Low-Carbon Conversion Science and Engineering, Shanghai Advanced Research Institute, Chinese Academy of Sciences, Shanghai, 201210, China.
⁶ Key Laboratory of Synthetic and Self-Assembly Chemistry for Organic Functional Molecules, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai, 200032, China.
⁷ Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai, 200438, China. zhuyifeng@fudan.edu.cn.
⁸ Department of Chemistry, Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Collaborative Innovation Center of Chemistry for Energy Materials, Fudan University, Shanghai, 200438, China. xhbao@dicp.ac.cn.
⁹ State Key Laboratory of Catalysis, National Laboratory for Clean Energy, Collaborative Innovation Center of Chemistry for Energy Materials, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, 116023, China. xhbao@dicp.ac.cn.

Abstract

The limited surface coverage and activity of active hydrides on oxide surfaces pose challenges for efficient hydrogenation reactions. Herein, we quantitatively distinguish the long-puzzling homolytic dissociation of hydrogen from the heterolytic pathway on Ga₂O₃, that is useful for enhancing hydrogenation ability of oxides. By combining transient kinetic analysis with infrared and mass spectroscopies, we identify the catalytic role of coordinatively unsaturated Ga³⁺ in homolytic H₂ dissociation, which is formed in-situ during the initial heterolytic dissociation. This site facilitates easy hydrogen dissociation at low temperatures, resulting in a high hydride coverage on Ga₂O₃ (H/surface Ga³⁺ ratio of 1.6 and H/OH ratio of 5.6). The effectiveness of homolytic dissociation is governed by the Ga-Ga distance, which is strongly influenced by the initial coordination of Ga³⁺. Consequently, by tuning the coordination of active Ga³⁺ species as well as the coverage and activity of hydrides, we achieve enhanced hydrogenation of CO₂ to CO, methanol or light olefins by 4-6 times.

Grants and funding

22CAA00915/National Natural Science Foundation of China (National Science Foundation of China)