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Wu L, Lin J, Ren L, Li QN, Chi X, Luo L, Zhang Y, Zeng MH. Electronic Structures of Hydroxyled Low Index Surfaces of Rutile and Anatase-Type Titanium Dioxide. Phys Chem Chem Phys 2022; 24:15091-15102. [DOI: 10.1039/d1cp04729a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Different surface planes of various types of TiO2 crystals have diverse catalysis effects on the splitting of H2O and H2 and the electronic structures of the formed hydroxylated titanium dioxide...
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Wei B, Tielens F, Calatayud M. Understanding the Role of Rutile TiO 2 Surface Orientation on Molecular Hydrogen Activation. NANOMATERIALS 2019; 9:nano9091199. [PMID: 31454939 PMCID: PMC6780095 DOI: 10.3390/nano9091199] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/23/2019] [Revised: 08/10/2019] [Accepted: 08/16/2019] [Indexed: 11/30/2022]
Abstract
Titanium oxide (TiO2) has been widely used in many fields, such as photocatalysis, photovoltaics, catalysis, and sensors, where its interaction with molecular H2 with TiO2 surface plays an important role. However, the activation of hydrogen over rutile TiO2 surfaces has not been systematically studied regarding the surface termination dependence. In this work, we use density functional theory (PBE+U) to identify the pathways for two processes: the heterolytic dissociation of H2 as a hydride–proton pair, and the subsequent H transfer from Ti to near O accompanied by reduction of the Ti sites. Four stoichiometric surface orientations were considered: (001), (100), (110), and (101). The lowest activation barriers are found for hydrogen dissociation on (001) and (110), with energies of 0.56 eV and 0.50 eV, respectively. The highest activation barriers are found on (100) and (101), with energies of 1.08 eV and 0.79 eV, respectively. For hydrogen transfer from Ti to near O, the activation barriers are higher (from 1.40 to 1.86 eV). Our results indicate that the dissociation step is kinetically more favorable than the H transfer process, although the latter is thermodynamically more favorable. We discuss the implications in the stability of the hydride–proton pair, and provide structures, electronic structure, vibrational analysis, and temperature effects to characterize the reactivity of the four TiO2 orientations.
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Affiliation(s)
- Baohuan Wei
- Sorbonne Université, CNRS, Laboratoire de Chimie Théorique, LCT, F. 75005 Paris, France
| | - Frederik Tielens
- General Chemistry (ALGC), Materials Modelling Group, Vrije Universiteit Brussel (Free University Brussels-VUB), Pleinlaan 2, 1050 Brussel, Belgium
| | - Monica Calatayud
- Sorbonne Université, CNRS, Laboratoire de Chimie Théorique, LCT, F. 75005 Paris, France.
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Shi Y, Sun H, Nguyen MC, Wang C, Ho K, Saidi WA, Zhao J. Structures of defects on anatase TiO 2(001) surfaces. NANOSCALE 2017; 9:11553-11565. [PMID: 28770922 DOI: 10.1039/c7nr02458d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Defects on oxide surfaces play a crucial role in surface reactivity and thus it is crucial to understand their atomic and electronic structures. The defects on anatase TiO2(001)-(1 × 4) surfaces are found to be highly reactive; however, due to the surface reconstruction, the defects exhibit a complicated character in different experiments that make it very challenging to determine their atomic structures. Here we present a systematic first-principles investigation of the defects on anatase TiO2(001)-(1 × 4) surfaces based on a global-search adaptive genetic algorithm (AGA) and density functional theory (DFT). For different Ti-O ratios, we identify the low energy defect structures, investigate their electronic structure using a hybrid functional, and map their regions of stability under realistic conditions. We successfully find novel oxygen vacancy (OV) and Ti interstitial (Tiini) structures that are different from the conventional ones in terms of their charge localization, magnetic state, and their scanning-tunneling-microscopy bright-dark image signature. This provides an insight into the complex geometric and electronic structure of the surface defects, and resolves several experimental discrepancies.
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Affiliation(s)
- Yongliang Shi
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale, and Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026, China.
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Shi Y, Sun H, Saidi WA, Nguyen MC, Wang CZ, Ho K, Yang J, Zhao J. Role of Surface Stress on the Reactivity of Anatase TiO 2(001). J Phys Chem Lett 2017; 8:1764-1771. [PMID: 28359150 DOI: 10.1021/acs.jpclett.7b00181] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
In contrast with theoretical predictions in which anatase TiO2(001) and its (1 × 4) reconstructed surfaces are highly reactive, recent experimental results show this surface to be inert except for the defect sites. In this report, based on a systematic study of anatase TiO2(001)-(1 × 4) surface using first-principles calculations, the tensile stress is shown to play a crucial role on the surface reactivity. The predicted high reactivity based on add-molecule model is due to the large surface tensile stress, which can be easily suppressed by a stress-release mechanism. We show that various surface defects can induce stress release concomitantly with surface passivation. Thus the synthesis of anatase(001) surface with few defects is essential to improve the reactivity, which can be achieved, for example, via H2O adsorption. Our study provides a uniform interpretation of controversial experimental observations and theoretical predictions on anatase TiO2(001) surface and further proposes new insights into the origin of surface reactivity.
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Affiliation(s)
- Yongliang Shi
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale and Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
| | - Huijuan Sun
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale and Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
- College of Physics, Qingdao University , Qingdao 266071, China
| | - Wissam A Saidi
- Department of Mechanical Engineering and Materials Science, University of Pittsburgh , Pittsburgh, Pennsylvania 15261, United States
| | - Manh Cuong Nguyen
- Ames Laboratory-US DOE and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - Cai Zhuang Wang
- Ames Laboratory-US DOE and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - Kaiming Ho
- Ames Laboratory-US DOE and Department of Physics and Astronomy, Iowa State University , Ames, Iowa 50011, United States
| | - Jinlong Yang
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale and Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
- Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
| | - Jin Zhao
- ICQD/Hefei National Laboratory for Physical Sciences at Microscale and Key Laboratory of Strongly-Coupled Quantum Matter Physics, Chinese Academy of Sciences, and Department of Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
- Department of Physics and Astronomy, University of Pittsburgh , Pittsburgh, Pennsylvania 15260, United States
- Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China , Hefei, Anhui 230026, China
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Deskins NA, Du J, Rao P. The structural and electronic properties of reduced amorphous titania. Phys Chem Chem Phys 2017; 19:18671-18684. [DOI: 10.1039/c7cp02940c] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Reduced amorphous titania has been modeled by removing oxygen atoms to clarify the properties of these materials.
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Affiliation(s)
- N. Aaron Deskins
- Department of Chemical Engineering
- Worcester Polytechnic Institute
- Worcester
- USA
| | - Jincheng Du
- Materials Science and Engineering
- University of North Texas
- Denton
- USA
| | - Pratap Rao
- Department of Mechanical Engineering
- Worcester Polytechnic Institute
- Worcester
- USA
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Zhang D, Yang M, Dong S. Electric-dipole effect of defects on the energy band alignment of rutile and anatase TiO2. Phys Chem Chem Phys 2015; 17:29079-84. [DOI: 10.1039/c5cp04495b] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
DFT+U calculations determined that the perfect rutile(110) and anatase(101) surfaces have the straddling type band alignment, whereas surfaces with defects have the staggered type.
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Affiliation(s)
- Daoyu Zhang
- Department of Physics & Jiangsu Key Laboratory for Advanced Metallic Materials
- Southeast University
- Nanjing
- China
| | - Minnan Yang
- Department of Physics
- China Pharmaceutical University
- Nanjing
- China
| | - Shuai Dong
- Department of Physics & Jiangsu Key Laboratory for Advanced Metallic Materials
- Southeast University
- Nanjing
- China
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