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Lai Y, Zeng Y, Li F, Chen X, Wang T, Guo Q. Wavelength-Dependent Activity of Oxygen Species in Propane Conversion on Rutile TiO 2(110). J Phys Chem Lett 2024; 15:6943-6951. [PMID: 38940377 DOI: 10.1021/acs.jpclett.4c01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/29/2024]
Abstract
Photocatalytic oxidative dehydrogenation of propane (C3H8) into propene (C3H6) under mild conditions holds great potential in the chemical industry, but understanding how active species participate in C3H8 conversion remains a significant challenge. Here, the wavelength-dependent activities of bridging oxygen (Ob2-) and the Ti5c-bound oxygen adatom (OTi2-) of model rutile (R) TiO2(110) in C3H8 conversion have been investigated. Under 257 and 343 nm irradiation, hole-trapped OTi- and Ob- can abstract the hydrogen atom of C3H8, forming the CH3CH•CH3 radical and C3H6. However, the rate of C3H8 conversion with hole-trapped Ob- is strongly dependent on the wavelength, primarily producing the C3H7• radical. In the case of hole-trapped OTi-, C3H6 is the main product, which is nearly independent of wavelength. The differences in the wavelength-dependent activity and product selectivity are likely due to dynamic control rather than thermodynamic control. The result provides a deeper understanding of the dynamic processes involved in the conversion of light alkanes in TiO2 photocatalysis.
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Affiliation(s)
- Yuemiao Lai
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
| | - Yi Zeng
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
| | - Fangliang Li
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
| | - Xiao Chen
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
- Institute of Advanced Science Facilities, Shenzhen, Guangdong 518107, P. R. China
| | - Tao Wang
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
| | - Qing Guo
- Shenzhen Key Laboratory of Energy Chemistry and Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
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2
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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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3
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Křenek T, Vála L, Medlín R, Pola J, Jandová V, Vavruňková V, Mikysek P, Bělský P, Koštejn M. A novel route of colloidal chemistry: room temperature reactive interactions between titanium monoxide and silicon monoxide sols produced by laser ablation in liquid resulting in the formation of titanium disilicide. Dalton Trans 2022; 51:13831-13847. [PMID: 36039852 DOI: 10.1039/d2dt02065c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
In spite of advanced research on functional colloidal inorganic nanoparticles and their reactivity, room temperature reactive interactions between two different colloids have remained challenging so far. Laser ablation of titanium monoxide and silicon monoxide in ethanol and water allows the generation of TiO-derived and SiO-derived colloidal nanoparticles which were characterized for their stability, size distribution and zeta potentials with dynamic light scattering and after evaporation of solvent examined for their morphology, chemical and phase composition by scanning electron microscopy, Raman spectroscopy, high resolution transmission electron microscopy and electron diffraction and small angle X-ray scattering. Aqueous and ethanolic TiO-derived colloids consist of anatase and monoclinic TiO, while ethanolic SiO-derived colloids are composed of crystalline and amorphous Si, nanocrystalline Si and SiO2 and aqueous SiO-derived colloids contain, in addition to these phases, a high pressure form of cristobalite. Simple room temperature mixing of ethanolic TiO- and SiO-derived colloids allows the formation of TiSi2, which is a case of so far unreported room temperature reactive interactions between two colloidal species. All colloids absorb solar light and act as photocatalysts for methylene blue degradation. These findings present a challenge for further search for feasible room-temperature reactions between distinct colloidal particles and open the potential for green synthesis of other desirable and hardly achievable phases.
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Affiliation(s)
- Tomáš Křenek
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic.
| | - Lukáš Vála
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic.
| | - Rostislav Medlín
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic.
| | - Josef Pola
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic. .,Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 135, 165 02, Prague 6, Czech Republic
| | - Věra Jandová
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic. .,Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 135, 165 02, Prague 6, Czech Republic
| | - Veronika Vavruňková
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic.
| | - Petr Mikysek
- Institute of Geology of the Czech Academy of Sciences, Rozvojová 269, 165 00, Praha 6, Czech Republic
| | - Petr Bělský
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic.
| | - Martin Koštejn
- New Technologies-Research Center, University of West Bohemia, Univerzitní 8, 306 14, Pilsen, Czech Republic. .,Institute of Chemical Process Fundamentals of the Czech Academy of Sciences, Rozvojová 135, 165 02, Prague 6, Czech Republic
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4
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Sun R, Liu X, Chen X, Che L, Yang X, Guo Q. One-Pot Ethyl Acetate Production from Ethanol Photooxidation on Rutile TiO 2(110): Strong Photon Energy Dependence. J Phys Chem Lett 2022; 13:801-807. [PMID: 35044191 DOI: 10.1021/acs.jpclett.2c00048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Ethyl acetate (EA) production from sequential ethanol (EtOH) photooxidation on a rutile(R)-TiO2(110) surface has been investigated by the temperature-programmed desorption (TPD) method at 355 and 266 nm. Significant EA product is detected under 266 nm irradiation, which is most likely to be formed via cross-coupling of primary dissociation products, aldehyde (CH3CHO) and ethoxy groups. On the contrary, EA formation at 355 nm is negligible. In addition, the initial rate of EA formation from EtOH at 266 nm is nearly 2 orders of magnitude faster than that at 355 nm. Quantitative analysis suggests that EA formation from sequential EtOH photooxidation on R-TiO2(110) is strongly dependent on photon energy or the energy of hot holes. This experimental result raises doubt about the traditional photocatalysis model on TiO2 where charge carriers relax to their respective band edges prior to charge transfer to adsorbates during the photocatalytic process, leading to no dependence on photon energy in TiO2 photocatalysis.
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Affiliation(s)
- Rulin Sun
- College of Environmental Sciences and Engineering, Dalian Maritime University, Dalian, Liaoning 116026, People's Republic of China
| | - Xinlu Liu
- College of Environmental Sciences and Engineering, Dalian Maritime University, Dalian, Liaoning 116026, People's Republic of China
| | - Xiao Chen
- Shenzhen Key Laboratory of Energy Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
| | - Li Che
- College of Environmental Sciences and Engineering, Dalian Maritime University, Dalian, Liaoning 116026, People's Republic of China
| | - Xueming Yang
- Shenzhen Key Laboratory of Energy Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People's Republic of China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
| | - Qing Guo
- Shenzhen Key Laboratory of Energy Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, People's Republic of China
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5
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Cionti C, Cosaert E, Deshayes G, Falletta E, Meroni D, Bianchi CL, Poelman D. Self-cleaning, photocatalytic films on aluminum plates for multi-pollutant air remediation: promoting adhesion and activity by SiO 2interlayers. NANOTECHNOLOGY 2021; 32:475710. [PMID: 34388747 DOI: 10.1088/1361-6528/ac1d76] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2021] [Accepted: 08/13/2021] [Indexed: 06/13/2023]
Abstract
In recent years, nanoparticles have come under close scrutiny for their possible health and environmental issues, making them less attractive for photocatalytic applications in air or water purification. Replacing free nano-powders with active and stable films is thus a fundamental step towards developing effective photocatalytic devices. Aluminum represents a cheap and technologically-relevant substrate, but its photocatalytic applications have been hampered by adhesion issues and metal ion diffusion within the photocatalytic layer. In this work, the use of silica interlayers is investigated as a strategy to promote adhesion, efficiency and reusability of TiO2films deposited on aluminum plates. Films were prepared from stable titania sols to avoid the use of nano-powders. Aluminum substrates with different surface morphology were investigated and the role of the silica interlayer thickness was studied. Films were extensively characterized, studying their structure, morphology, optical properties, adhesion and hardness. Self-cleaning properties were studied with respect to their superhydrophilicity and ability to resist fouling via alkylsilanes. Photocatalytic degradation tests were carried out using both volatile organic compounds and NOx, also in recycle tests. The presence of the silica interlayer proved crucial to promote the film robustness and photocatalytic activity. The substrate morphology determined the optimal interlayer thickness, especially in terms of the film reusability.
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Affiliation(s)
- Carolina Cionti
- Università degli Studi di Milano, Department of Chemistry, Milan, Italy
- Consorzio INSTM, Florence, Italy
| | - Ewoud Cosaert
- Ghent University, Department of Solid State Sciences, Ghent, Belgium
| | - Gabriele Deshayes
- Università degli Studi di Milano, Department of Chemistry, Milan, Italy
| | - Ermelinda Falletta
- Università degli Studi di Milano, Department of Chemistry, Milan, Italy
- Consorzio INSTM, Florence, Italy
| | - Daniela Meroni
- Università degli Studi di Milano, Department of Chemistry, Milan, Italy
- Consorzio INSTM, Florence, Italy
| | - Claudia L Bianchi
- Università degli Studi di Milano, Department of Chemistry, Milan, Italy
- Consorzio INSTM, Florence, Italy
| | - Dirk Poelman
- Ghent University, Department of Solid State Sciences, Ghent, Belgium
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6
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Dong S, Hu J, Xia S, Wang B, Wang Z, Wang T, Chen W, Ren Z, Fan H, Dai D, Cheng J, Yang X, Zhou C. Origin of the Adsorption-State-Dependent Photoactivity of Methanol on TiO 2(110). ACS Catal 2021. [DOI: 10.1021/acscatal.0c03930] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Shanshan Dong
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Jinyuan Hu
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Shucai Xia
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Binli Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Zhiqiang Wang
- School of Physics and Optoelectronic Engineering, Xidian University, Xi’an 710071, P. R. China
| | - Tianjun Wang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Wei Chen
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
| | - Zefeng Ren
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Hongjun Fan
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Dongxu Dai
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Jun Cheng
- State Key Laboratory of Physical Chemistry of Solid Surfaces, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Road, Shenzhen, Guangdong 518055, P. R. China
| | - Chuanyao Zhou
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Science, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- University of Chinese Academy of Sciences, No.19A Yuquan Road, Shijingshan District, Beijing 100049, P. R. China
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7
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Courtois C, Walenta CA, Tschurl M, Heiz U, Friend CM. Regulating Photochemical Selectivity with Temperature: Isobutanol on TiO 2(110). J Am Chem Soc 2020; 142:13072-13080. [PMID: 32598843 DOI: 10.1021/jacs.0c04411] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Selective photocatalytic transformations of chemicals derived from biomass, such as isobutanol, have been long envisioned for a sustainable chemical production. A strong temperature dependence in the reaction selectivity is found for isobutanol photo-oxidation on rutile TiO2(110). The strong temperature dependence is attributed to competition between thermal desorption of the primary photoproduct and secondary photochemical steps. The aldehyde, isobutanal, is the primary photoproduct of isobutanol. At room temperature, isobutanal is obtained selectively from photo-oxidation because of rapid thermal desorption. In contrast, secondary photo-oxidation of isobutanal to propane dominates at lower temperature (240 K) due to the persistence of isobutanal on the surface after it is formed. The byproduct of isobutanal photo-oxidation is CO, which is evolved at higher temperature as a consequence of thermal decomposition of an intermediate, such as formate. The photo-oxidation to isobutanal proceeds after thermally induced isobutoxy formation. These results have strong implications for controlling the selectivity of photochemical processes more generally, in that, selectivity is governed by competition of desorption vs secondary photoreaction of products. This competition can be exploited to design photocatalytic processes to favor specific chemical transformations of organic molecules.
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Affiliation(s)
- Carla Courtois
- Chair of Physical Chemistry & Catalysis Research Center, Technical University of Munich, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Constantin A Walenta
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
| | - Martin Tschurl
- Chair of Physical Chemistry & Catalysis Research Center, Technical University of Munich, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Ueli Heiz
- Chair of Physical Chemistry & Catalysis Research Center, Technical University of Munich, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Cynthia M Friend
- Department of Chemistry and Chemical Biology, Harvard University, 12 Oxford Street, Cambridge, Massachusetts 02138, United States
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8
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Courtois C, Eder M, Kollmannsberger SL, Tschurl M, Walenta CA, Heiz U. Origin of Poisoning in Methanol Photoreforming on TiO2(110): The Importance of Thermal Back-Reaction Steps in Photocatalysis. ACS Catal 2020. [DOI: 10.1021/acscatal.0c01615] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Carla Courtois
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Moritz Eder
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Sebastian L. Kollmannsberger
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Martin Tschurl
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Constantin A. Walenta
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Ueli Heiz
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
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9
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Wu L, Fu C, Huang W. Surface chemistry of TiO 2 connecting thermal catalysis and photocatalysis. Phys Chem Chem Phys 2020; 22:9875-9909. [PMID: 32363360 DOI: 10.1039/c9cp07001j] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Chemical reactions catalyzed under heterogeneous conditions have recently expanded rapidly from traditional thermal catalysis to photocatalysis due to the rising concerns about sustainable development of energy and the environment. Adsorption of reactants on catalyst surfaces, subsequent surface reactions, and desorption of products from catalyst surfaces occur in both thermal catalysis and photocatalysis. TiO2 catalysts are widely used in thermal catalytic and photocatalytic reactions. Herein we review recent progress in surface chemistry, thermal catalysis and photocatalysis of TiO2 model catalysts from single crystals to nanocrystals with the aim of examining if the surface chemistry of TiO2 can bridge the fundamental understanding between thermal catalysis and photocatalysis. Following a brief introduction, the structures of major facets exposed on TiO2 catalysts, including surface reconstructions and defects, as well as the electronic structure and charge properties, are firstly summarized; then the recent progress in adsorption, thermal chemistry and photochemistry of small molecules on TiO2 single crystals and nanocrystals is comprehensively reviewed, focusing on manifesting the structure-(photo)activity relations and the commonalities/differences between thermal catalysis and photocatalysis; and finally concluding remarks and perspectives are given.
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Affiliation(s)
- Longxia Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, P. R. China.
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10
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Guo Q, Zhou C, Ma Z, Yang X. Fundamentals of TiO 2 Photocatalysis: Concepts, Mechanisms, and Challenges. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2019; 31:e1901997. [PMID: 31423680 DOI: 10.1002/adma.201901997] [Citation(s) in RCA: 433] [Impact Index Per Article: 86.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Revised: 07/23/2019] [Indexed: 05/27/2023]
Abstract
Photocatalysis has been widely applied in various areas, such as solar cells, water splitting, and pollutant degradation. Therefore, the photochemical mechanisms and basic principles of photocatalysis, especially TiO2 photocatalysis, have been extensively investigated by various surface science methods in the last decade, aiming to provide important information for TiO2 photocatalysis under real environmental conditions. Recent progress that provides fundamental insights into TiO2 photocatalysis at a molecular level is highlighted. Insights into the structures of TiO2 and the basic principles of TiO2 photocatalysis are discussed first, which provides the basic concepts of TiO2 photocatalysis. Following this, details of the photochemistry of three important molecules (oxygen, water, methanol) on the model TiO2 surfaces are presented, in an attempt to unravel the relationship between charge/energy transfer and bond breaking/forming in TiO2 photocatalysis. Lastly, challenges and opportunities of the mechanistic studies of TiO2 photocatalysis at the molecular level are discussed briefly, as well as possible photocatalysis models.
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Affiliation(s)
- Qing Guo
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023, China
- Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Avenue, Shenzhen, 518055, China
| | - Chuanyao Zhou
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023, China
| | - Zhibo Ma
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023, China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Road, Dalian, Liaoning, 116023, China
- Department of Chemistry, Southern University of Science and Technology, 1088 Xueyuan Avenue, Shenzhen, 518055, China
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11
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Walenta CA, Tschurl M, Heiz U. Introducing catalysis in photocatalysis: What can be understood from surface science studies of alcohol photoreforming on TiO 2. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:473002. [PMID: 31342942 DOI: 10.1088/1361-648x/ab351a] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Mechanisms in heterogeneous photocatalysis have traditionally been interpreted by the band-structure model and analogously to electrochemistry. This has led to the establishment of 'band-engineering' as a leading principle for the discovery of more efficient photocatalysts. In such a picture, mainly thermodynamic aspects are taken into account, while kinetics are often ignored. This holds in particular for chemical kinetics, which are, other than those for charge carrier dynamics, often not at all considered for the interpretation of the catalysts' photocatalytic performance. However, while being usually neglected in photocatalyis, they are a traditional and powerful tool in thermal catalysis and are still applied with great success in this field. While surface science studies made substantial contributes to thermal catalysis, analogous studies in heterogeneous photocatalysis still play only a minor role. In this review, the authors show that the photo-physics of defined materials in well-defined environments can be correlated with photochemical events on a surface, highlighting the importance of well-characterized semiconductors for the interpretation of mechanisms in heterogeneous photochemistry. The work focuses on contributions from surface science, which were obtained for the model system of a titania single crystal and alcohol photo-reforming. It is demonstrated that only surface science studies have so far enabled the elucidation of molecularly precise reaction mechanisms, the determination of reaction intermediates and assignment of reactive sites. As the identification of these properties remain major prerequisites for a breakthrough in photocatalysis research, the work also discusses the implications of the findings for applied systems. In general, the results from surface science demonstrate that photocatalytic systems shall also be approached by a perspective originating from heterogeneous catalysis rather than solely from an electrochemical point of view.
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12
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Guo Q, Ma Z, Zhou C, Ren Z, Yang X. Single Molecule Photocatalysis on TiO2 Surfaces. Chem Rev 2019; 119:11020-11041. [DOI: 10.1021/acs.chemrev.9b00226] [Citation(s) in RCA: 129] [Impact Index Per Article: 25.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Qing Guo
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
| | - Zhibo Ma
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Chuanyao Zhou
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Zefeng Ren
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
| | - Xueming Yang
- State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, 457 Zhongshan Road, Dalian, Liaoning 116023, P. R. China
- Department of Chemistry, Southern University of Science and Technology, Shenzhen, Guangdong 518055, P. R. China
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13
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Katsiev K, Harrison G, Al-Salik Y, Thornton G, Idriss H. Gold Cluster Coverage Effect on H2 Production over Rutile TiO2(110). ACS Catal 2019. [DOI: 10.1021/acscatal.9b01890] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- K. Katsiev
- Fundamental Catalysis, SABIC-CRD at KAUST, Thuwal, Saudi Arabia
| | - G. Harrison
- Department of Chemistry and London Centre for Nanotechnology, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - Y. Al-Salik
- Fundamental Catalysis, SABIC-CRD at KAUST, Thuwal, Saudi Arabia
| | - G. Thornton
- Department of Chemistry and London Centre for Nanotechnology, University College London, 20 Gordon Street, London WC1H 0AJ, U.K
| | - H. Idriss
- Fundamental Catalysis, SABIC-CRD at KAUST, Thuwal, Saudi Arabia
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14
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Al-Azri ZHN, AlOufi M, Chan A, Waterhouse GIN, Idriss H. Metal Particle Size Effects on the Photocatalytic Hydrogen Ion Reduction. ACS Catal 2019. [DOI: 10.1021/acscatal.8b05070] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Z. H. N. Al-Azri
- School of Chemical Sciences, The University of Auckland, Private Bag
92019, Auckland 1142, New Zealand
- Department of Chemistry, College of Science, Sultan Qaboos University, P.O. Box 36, Al-Khod 123, Oman
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - M. AlOufi
- Corporate Research and Development (CRD), Saudi Basic Industries Corporation (SABIC), KAUST, Thuwal 23955-6900, Saudi Arabia
| | - A. Chan
- School of Chemical Sciences, The University of Auckland, Private Bag
92019, Auckland 1142, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - G. I. N. Waterhouse
- School of Chemical Sciences, The University of Auckland, Private Bag
92019, Auckland 1142, New Zealand
- The MacDiarmid Institute for Advanced Materials and Nanotechnology, Wellington 6140, New Zealand
| | - H. Idriss
- Corporate Research and Development (CRD), Saudi Basic Industries Corporation (SABIC), KAUST, Thuwal 23955-6900, Saudi Arabia
- Department of Chemistry, University College London, London WC1E 6BT, U.K
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15
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Walenta CA, Kollmannsberger SL, Courtois C, Pereira RN, Stutzmann M, Tschurl M, Heiz U. Why co-catalyst-loaded rutile facilitates photocatalytic hydrogen evolution. Phys Chem Chem Phys 2019; 21:1491-1496. [DOI: 10.1039/c8cp05513k] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photocatalytic H2 evolution on co-catalyst loaded titania is interpreted by a new mechanism, in which the co-catalyst acts as a recombination center for hydrogen and not as a reduction site of a photoreaction.
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Affiliation(s)
- Constantin A. Walenta
- Chair of Physical Chemistry
- Department of Chemistry & Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
| | - Sebastian L. Kollmannsberger
- Chair of Physical Chemistry
- Department of Chemistry & Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
| | - Carla Courtois
- Chair of Physical Chemistry
- Department of Chemistry & Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
| | - Rui N. Pereira
- Walter Schottky Institute and Physics Department
- Technische Universität München
- 85748 Garching
- Germany
| | - Martin Stutzmann
- Nanosystems Initiative Munich
- 80799 München
- Germany
- Walter Schottky Institute and Physics Department
- Technische Universität München
| | - Martin Tschurl
- Chair of Physical Chemistry
- Department of Chemistry & Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
| | - Ueli Heiz
- Chair of Physical Chemistry
- Department of Chemistry & Catalysis Research Center
- Technische Universität München
- 85748 Garching
- Germany
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16
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The Mechanism of Adsorption, Diffusion, and Photocatalytic Reaction of Organic Molecules on TiO2 Revealed by Means of On-Site Scanning Tunneling Microscopy Observations. Catalysts 2018. [DOI: 10.3390/catal8120616] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
The interaction of organic molecules and titanium dioxide (TiO2) plays a crucial role in many industry-oriented applications and an understanding of its mechanism can be helpful for the improvement of catalytic efficiency of TiO2. Scanning tunneling microscopy (STM) has been proved to be a powerful tool in characterizing reaction pathways due to its ability in providing on-site images during the catalytic process. Over the past two decades, many research interests have been focused on the elementary reaction steps, such as adsorption, diffusion, and photocatalytic reaction, occurring between organic molecules and model TiO2 surfaces. This review collects the recent studies where STM was utilized to study the interaction of TiO2 with three classes of representative organic molecules, i.e., alcohols, carboxylic acids, and aromatic compounds. STM can provide direct evidence for the adsorption configuration, diffusion route, and photocatalytic pathway. In addition, the combination of STM with other techniques, including photoemission spectroscopy (PES), temperature programmed desorption (TPD), and density functional theory (DFT), have been discussed for more insights related to organic molecules-TiO2 interaction.
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17
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Kollmannsberger SL, Walenta CA, Courtois C, Tschurl M, Heiz U. Thermal Control of Selectivity in Photocatalytic, Water-Free Alcohol Photoreforming. ACS Catal 2018. [DOI: 10.1021/acscatal.8b03479] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Sebastian L. Kollmannsberger
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Constantin A. Walenta
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
- Nanosystems Initiative Munich, Schellingstraße 4, 80799 München, Germany
| | - Carla Courtois
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Martin Tschurl
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
| | - Ueli Heiz
- Chair of Physical Chemistry, Department of Chemistry & Catalysis Research Center, Technische Universität München, Lichtenbergstraße 4, 85748 Garching, Germany
- Nanosystems Initiative Munich, Schellingstraße 4, 80799 München, Germany
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18
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Switch in photocatalytic reaction selectivity: The effect of oxygen partial pressure on carbon-carbon bond dissociation over hydroxylated TiO2(1 1 0) surfaces. J Catal 2018. [DOI: 10.1016/j.jcat.2018.04.015] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Muñoz-Santiburcio D, Farnesi Camellone M, Marx D. Solvation-Induced Changes in the Mechanism of Alcohol Oxidation at Gold/Titania Nanocatalysts in the Aqueous Phase versus Gas Phase. Angew Chem Int Ed Engl 2018; 57:3327-3331. [DOI: 10.1002/anie.201710791] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/08/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Daniel Muñoz-Santiburcio
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
- Present address: CIC nanoGUNE; Tolosa Hiribidea 76 20018 San Sebastián Spain
| | | | - Dominik Marx
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
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20
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Muñoz-Santiburcio D, Farnesi Camellone M, Marx D. Solvation-Induced Changes in the Mechanism of Alcohol Oxidation at Gold/Titania Nanocatalysts in the Aqueous Phase versus Gas Phase. Angew Chem Int Ed Engl 2018. [DOI: 10.1002/ange.201710791] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Daniel Muñoz-Santiburcio
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
- Present address: CIC nanoGUNE; Tolosa Hiribidea 76 20018 San Sebastián Spain
| | | | - Dominik Marx
- Lehrstuhl für Theoretische Chemie; Ruhr-Universität Bochum; 44780 Bochum Germany
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21
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Nadeem MA, Idriss H. Photo-thermal reactions of ethanol over Ag/TiO2 catalysts. The role of silver plasmon resonance in the reaction kinetics. Chem Commun (Camb) 2018; 54:5197-5200. [DOI: 10.1039/c8cc01814f] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Photo-thermal catalytic reactions of ethanol over Ag/TiO2 were conducted in order to probe into the role of plasmonic resonance response in the reaction kinetics.
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Affiliation(s)
- M. A. Nadeem
- Corporate Research & Development (CRD)
- Saudi Basic Industries Corporation (SABIC) KAUST
- Thuwal 23955-6900
- Saudi Arabia
| | - H. Idriss
- Corporate Research & Development (CRD)
- Saudi Basic Industries Corporation (SABIC) KAUST
- Thuwal 23955-6900
- Saudi Arabia
- Department of Chemistry
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22
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Setvin M, Shi X, Hulva J, Simschitz T, Parkinson GS, Schmid M, Di Valentin C, Selloni A, Diebold U. Methanol on Anatase TiO 2 (101): Mechanistic Insights into Photocatalysis. ACS Catal 2017; 7:7081-7091. [PMID: 29034122 PMCID: PMC5634753 DOI: 10.1021/acscatal.7b02003] [Citation(s) in RCA: 51] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 08/29/2017] [Indexed: 01/06/2023]
Abstract
The photoactivity of methanol adsorbed on the anatase TiO2 (101) surface was studied by a combination of scanning tunneling microscopy (STM), temperature-programmed desorption (TPD), X-ray photoemission spectroscopy (XPS), and density functional theory (DFT) calculations. Isolated methanol molecules adsorbed at the anatase (101) surface show a negligible photoactivity. Two ways of methanol activation were found. First, methoxy groups formed by reaction of methanol with coadsorbed O2 molecules or terminal OH groups are photoactive, and they turn into formaldehyde upon UV illumination. The methoxy species show an unusual C 1s core-level shift of 1.4 eV compared to methanol; their chemical assignment was verified by DFT calculations with inclusion of final-state effects. The second way of methanol activation opens at methanol coverages above 0.5 monolayer (ML), and methyl formate is produced in this reaction pathway. The adsorption of methanol in the coverage regime from 0 to 2 ML is described in detail; it is key for understanding the photocatalytic behavior at high coverages. There, a hydrogen-bonding network is established in the adsorbed methanol layer, and consequently, methanol dissociation becomes energetically more favorable. DFT calculations show that dissociation of the methanol molecule is always the key requirement for hole transfer from the substrate to the adsorbed methanol. We show that the hydrogen-bonding network established in the methanol layer dramatically changes the kinetics of proton transfer during the photoreaction.
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Affiliation(s)
- Martin Setvin
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
| | - Xiao Shi
- Department
of Chemistry, Princeton University, Frick
Laboratory, Princeton, New Jersey 08544, United States
| | - Jan Hulva
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
| | - Thomas Simschitz
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
| | - Gareth S. Parkinson
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
| | - Michael Schmid
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
| | - Cristiana Di Valentin
- Dipartimento
di Scienza dei Materiali, Università
di Milano-Bicocca, Via
Cozzi 55, 20125 Milano, Italy
| | - Annabella Selloni
- Department
of Chemistry, Princeton University, Frick
Laboratory, Princeton, New Jersey 08544, United States
| | - Ulrike Diebold
- Institute
of Applied Physics, TU Wien, Wiedner Hauptstrasse 8-10/134, 1040 Vienna, Austria
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23
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Jin X, Li C, Xu C, Guan D, Cheruvathur A, Wang Y, Xu J, Wei D, Xiang H, (Hans) Niemantsverdriet J, Li Y, Guo Q, Ma Z, Su R, Yang X. Photocatalytic C C bond cleavage in ethylene glycol on TiO2: A molecular level picture and the effect of metal nanoparticles. J Catal 2017. [DOI: 10.1016/j.jcat.2017.08.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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24
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Huang R, Liang R, Fan H, Ying S, Wu L, Wang X, Yan G. Enhanced Photocatalytic Fuel Denitrification over TiO 2/α-Fe 2O 3 Nanocomposites under Visible Light Irradiation. Sci Rep 2017; 7:7858. [PMID: 28798353 PMCID: PMC5552819 DOI: 10.1038/s41598-017-08439-3] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 07/11/2017] [Indexed: 11/09/2022] Open
Abstract
With increasingly stringent environmental regulations, the removal of nitrogen-containing compounds (NCCs) from gasoline fuel has become a more and more important research subject. In this work, we have successfully synthesized TiO2/α-Fe2O3 heterogeneous photocatalysts with different mass ratios of TiO2 vs. α-Fe2O3. Taking photocatalytic denitrification of typical alkali NCCs, pyridine, in gasoline fuel under visible light irradiation (λ ≥ 420 nm) as the model reaction, the TiO2/α-Fe2O3 hybrids have exhibited enhanced photocatalytic activity compared with pure TiO2 and α-Fe2O3, giving a pyridine removal ratio of ∼100% after irradiation for 240 min. The improved photocatalytic performance can be attributed to the integrative effect of the enhanced light absorption intensity and more efficient separation of photogenerated electron-hole pairs. Importantly, this type of heterogeneous photocatalysts can be easily separate in the reaction medium by an external magnetic field that is very important for industrial purpose. In addition, major reaction intermediates have been identified by the liquid chromatograph-mass spectrometer (HPLC-MS) and a tentative photocatalytic denitrification mechanism has been proposed.
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Affiliation(s)
- Renkun Huang
- Department of chemistry, Fujian province university key laboratory of green energy and environment catalysis, Ningde Normal University, Ningde, 352100, P.R. China
| | - Ruowen Liang
- Department of chemistry, Fujian province university key laboratory of green energy and environment catalysis, Ningde Normal University, Ningde, 352100, P.R. China
| | - Haimei Fan
- Department of chemistry, Fujian province university key laboratory of green energy and environment catalysis, Ningde Normal University, Ningde, 352100, P.R. China
| | - Shaoming Ying
- Department of chemistry, Fujian province university key laboratory of green energy and environment catalysis, Ningde Normal University, Ningde, 352100, P.R. China
| | - Ling Wu
- State key laboratory of photocatalysis on energy and environment, Fuzhou University, Fuzhou, 350002, P.R. China
| | - Xuxu Wang
- State key laboratory of photocatalysis on energy and environment, Fuzhou University, Fuzhou, 350002, P.R. China
| | - Guiyang Yan
- Department of chemistry, Fujian province university key laboratory of green energy and environment catalysis, Ningde Normal University, Ningde, 352100, P.R. China.
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25
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Olszowski P, Zajac L, Godlewski S, Such B, Pawlak R, Hinaut A, Jöhr R, Glatzel T, Meyer E, Szymonski M. Ordering of Zn-centered porphyrin and phthalocyanine on TiO 2(011): STM studies. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:99-107. [PMID: 28144569 PMCID: PMC5238625 DOI: 10.3762/bjnano.8.11] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Accepted: 12/21/2016] [Indexed: 05/04/2023]
Abstract
Zn(II)phthalocyanine molecules (ZnPc) were thermally deposited on a rutile TiO2(011) surface and on Zn(II)meso-tetraphenylporphyrin (ZnTPP) wetting layers at room temperature and after elevated temperature thermal processing. The molecular homo- and heterostructures were characterized by high-resolution scanning tunneling microscopy (STM) at room temperature and their geometrical arrangement and degree of ordering are compared with the previously studied copper phthalocyanine (CuPc) and ZnTPP heterostructures. It was found that the central metal atom may play some role in ordering and growth of phthalocyanine/ZnTPP heterostructures, causing differences in stability of upright standing ZnPc versus CuPc molecular chains at given thermal annealing conditions.
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Affiliation(s)
- Piotr Olszowski
- Research Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland
| | - Lukasz Zajac
- Research Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland
| | - Szymon Godlewski
- Research Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland
| | - Bartosz Such
- Research Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland
| | - Rémy Pawlak
- University of Basel, Department of Physics, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Antoine Hinaut
- University of Basel, Department of Physics, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Res Jöhr
- University of Basel, Department of Physics, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Thilo Glatzel
- University of Basel, Department of Physics, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Ernst Meyer
- University of Basel, Department of Physics, Klingelbergstrasse 82, 4056 Basel, Switzerland
| | - Marek Szymonski
- Research Centre for Nanometer-Scale Science and Advanced Materials, NANOSAM, Faculty of Physics, Astronomy, and Applied Computer Science, Jagiellonian University, Lojasiewicza 11, 30-348 Krakow, Poland
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26
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Zhang Y, Zhang CR, Wang W, Gong JJ, Liu ZJ, Chen HS. Density functional theory study of α-cyanoacrylic acid adsorbed on rutile TiO 2 (1 1 0) surface. COMPUT THEOR CHEM 2016. [DOI: 10.1016/j.comptc.2016.09.024] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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27
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Zuo ZJ, Peng F, Huang W. Efficient Synthesis of Ethanol from CH 4 and Syngas on a Cu-Co/TiO 2 Catalyst Using a Stepwise Reactor. Sci Rep 2016; 6:34670. [PMID: 27694944 PMCID: PMC5046147 DOI: 10.1038/srep34670] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 09/16/2016] [Indexed: 11/08/2022] Open
Abstract
Ethanol synthesis from CH4 and syngas on a Cu-Co/TiO2 catalyst is studied using experiments, density functional theory (DFT) and microkinetic modelling. The experimental results indicate that the active sites of ethanol synthesis from CH4 and syngas are Cu and CoO, over which the ethanol selectivity is approximately 98.30% in a continuous stepwise reactor. DFT and microkinetic modelling results show that *CH3 is the most abundant species and can be formed from *CH4 dehydrogenation or through the process of *CO hydrogenation. Next, the insertion of *CO into *CH3 forms *CH3CO. Finally, ethanol is formed through *CH3CO and *CH3COH hydrogenation. According to our results, small particles of metallic Cu and CoO as well as a strongly synergistic effect between metallic Cu and CoO are beneficial for ethanol synthesis from CH4 and syngas on a Cu-Co/TiO2 catalyst.
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Affiliation(s)
- Zhi-Jun Zuo
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
| | - Fen Peng
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
- Key Laboratory of Renewable Energy and Gas Hydrate, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou, China
| | - Wei Huang
- Key Laboratory of Coal Science and Technology of Ministry of Education and Shanxi Province, Taiyuan University of Technology, Taiyuan 030024, Shanxi, China
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