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Hu Z, Zhu J, Chen R, Wu Y, Zheng K, Liu C, Pan Y, Chen J, Sun Y, Xie Y. High-Rate and Selective C 2H 6-to-C 2H 4 Photodehydrogenation Enabled by Partially Oxidized Pd δ+ Species Anchored on ZnO Nanosheets under Mild Conditions. J Am Chem Soc 2024. [PMID: 38842530 DOI: 10.1021/jacs.4c02827] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2024]
Abstract
Photocatalytic C2H6-to-C2H4 conversion is very promising, yet it remains a long-lasting challenge due to the high C-H bond dissociation energy of 420 kJ mol-1. Herein, partially oxidized Pdδ+ species anchored on ZnO nanosheets are designed to weaken the C-H bond by the electron interaction between Pdδ+ species and H atoms, with efforts to achieve high-rate and selective C2H6-to-C2H4 conversion. X-ray photoelectron spectra, Bader charge calculations, and electronic localization function demonstrate the presence of partially oxidized Pdδ+ sites, while quasi-in situ X-ray photoelectron spectra disclose the Pdδ+ sites initially adopt and then donate the photoexcited electrons for C2H6 dehydrogenation. In situ electron paramagnetic resonance spectra, in situ Fourier transform infrared spectra, and trapping agent experiments verify C2H6 initially converts to CH3CH2OH via ·OH radicals, then dehydroxylates to CH3CH2· and finally to C2H4, accompanied by H2 production. Density-functional theory calculations elucidate that loading Pd site can lengthen the C-H bond of C2H6 from 1.10 to 1.12 Å, which favors the C-H bond breakage, affirmed by a lowered energy barrier of 0.04 eV. As a result, the optimized 5.87% Pd-ZnO nanosheets achieve a high C2H4 yield of 16.32 mmol g-1 with a 94.83% selectivity as well as a H2 yield of 14.49 mmol g-1 from C2H6 dehydrogenation in 4 h, outperforming all the previously reported photocatalysts under similar conditions.
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Affiliation(s)
- Zexun Hu
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Juncheng Zhu
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Runhua Chen
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Yang Wu
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Kai Zheng
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Chengyuan Liu
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
| | - Yang Pan
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China
| | - Jiafu Chen
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Yongfu Sun
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
| | - Yi Xie
- Hefei National Research Center for Physical Science at Microscale, University of Science and Technology of China, Hefei 230026, China
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Liu Y, Xue W, Liu X, Wei F, Lin X, Lu XF, Lin W, Hou Y, Zhang G, Wang S. Ultrafine Pt Nanoparticles on Defective Tungsten Oxide for Photocatalytic Ethylene Synthesis. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2024:e2402004. [PMID: 38686672 DOI: 10.1002/smll.202402004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2024] [Revised: 04/18/2024] [Indexed: 05/02/2024]
Abstract
The selective conversion of ethane (C2H6) to ethylene (C2H4) under mild conditions is highly wanted, yet very challenging. Herein, it is demonstrated that a Pt/WO3-x catalyst, constructed by supporting ultrafine Pt nanoparticles on the surface of oxygen-deficient tungsten oxide (WO3-x) nanoplates, is efficient and reusable for photocatalytic C2H6 dehydrogenation to produce C2H4 with high selectivity. Specifically, under pure light irradiation, the optimized Pt/WO3-x photocatalyst exhibits C2H4 and H2 yield rates of 291.8 and 373.4 µmol g-1 h-1, respectively, coupled with a small formation of CO (85.2 µmol g-1 h-1) and CH4 (19.0 µmol g-1 h-1), corresponding to a high C2H4 selectivity of 84.9%. Experimental and theoretical studies reveal that the vacancy-rich WO3-x catalyst enables broad optical harvesting to generate charge carriers by light for working the redox reactions. Meanwhile, the Pt cocatalyst reinforces adsorption of C2H6, desorption of key reaction species, and separation and migration of light-induced charges to promote the dehydrogenation reaction with high productivity and selectivity. In situ diffuse reflectance infrared Fourier transform spectroscopy and density functional theory calculation expose the key intermediates formed on the Pt/WO3-x catalyst during the reaction, which permits the construction of the possible C2H6 dehydrogenation mechanism.
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Affiliation(s)
- Yue Liu
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Weichao Xue
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Xiaoqing Liu
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Fen Wei
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Xiahui Lin
- College of Environment and Safety Engineering, Fuzhou University, Fuzhou, 350108, China
| | - Xue Feng Lu
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Wei Lin
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Yidong Hou
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Guigang Zhang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
| | - Sibo Wang
- State Key Laboratory of Photocatalysis on Energy and Environment, College of Chemistry, Fuzhou University, Fuzhou, 350116, P. R. China
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Li F, Lai Y, Zeng Y, Chen X, Wang T, Yang X, Guo Q. Photocatalytic ethane conversion on rutile TiO 2(110): identifying the role of the ethyl radical. Chem Sci 2023; 15:307-316. [PMID: 38131087 PMCID: PMC10732131 DOI: 10.1039/d3sc05623f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2023] [Accepted: 11/24/2023] [Indexed: 12/23/2023] Open
Abstract
Oxidative dehydrogenation of ethane (C2H6, ODHE) is a promising approach to producing ethene (C2H4) in the chemical industry. However, the ODHE needs to be operated at a high temperature, and realizing the ODHE under mild conditions is still a big challenge. Herein, using photocatalytic ODHE to obtain C2H4 has been achieved successfully on a model rutile(R)-TiO2(110) surface with high selectivity. Initially, the C2H6 reacts with hole trapped OTi- centers to produce ethyl radicals , which can be precisely detected by a sensitive TOF method, and then the majority of the radicals spontaneously dehydrogenate into C2H4 without another photo-generated hole. In addition, parts of the radicals rebound with diversified surface sites to produce C2 products via migration along the surface. The mechanistic model built in this work not only advances our knowledge of the C-H bond activation and low temperature C2H6 conversion, but also provides new opportunities for realizing the ODHE with high C2H4 efficiency under mild conditions.
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Affiliation(s)
- Fangliang Li
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
| | - Yuemiao Lai
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
| | - Yi Zeng
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
| | - Xiao Chen
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
| | - Tao Wang
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
| | - Xueming Yang
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences Dalian Liaoning 116023 PR China
- Hefei National Laboratory Hefei 230088 PR China
| | - Qing Guo
- Shenzhen Key Laboratory of Energy Chemistry & Department of Chemistry, Southern University of Science and Technology Shenzhen Guangdong 518055 PR China
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Wei F, Xue W, Yu Z, Lu XF, Wang S, Lin W, Wang X. Dynamic cooperations between lattice oxygen and oxygen vacancies for photocatalytic ethane dehydrogenation by a self-restoring LaVO4 catalyst. CHINESE CHEM LETT 2023. [DOI: 10.1016/j.cclet.2023.108313] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/13/2023]
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