201
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Ke TY, Chen PC, Yang MH, Chiu HT, Lee CY. Photo-induced nucleation of rutile nanorods—an ignored parameter in crystallization. CrystEngComm 2011. [DOI: 10.1039/c1ce05317e] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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202
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Jiao J, Chen L, Kuang D, Gao W, Feng H, Xia J. Synthesis of FeS2 and Co-doped FeS2 films with the aid of supercritical carbon dioxide and their photoelectrochemical properties. RSC Adv 2011. [DOI: 10.1039/c1ra00066g] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023] Open
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203
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204
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Castillo NC, Ding L, Heel A, Graule T, Pulgarin C. On the photocatalytic degradation of phenol and dichloroacetate by BiVO4: The need of a sacrificial electron acceptor. J Photochem Photobiol A Chem 2010. [DOI: 10.1016/j.jphotochem.2010.08.021] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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205
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Li YF, Liu ZP, Liu L, Gao W. Mechanism and Activity of Photocatalytic Oxygen Evolution on Titania Anatase in Aqueous Surroundings. J Am Chem Soc 2010; 132:13008-15. [DOI: 10.1021/ja105340b] [Citation(s) in RCA: 280] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Ye-Fei Li
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Key Laboratory for Computational Physical Sciences, Ministry of Education, Fudan University, Shanghai 200433, China, and School of Mathematical Sciences, Fudan University, Shanghai 200433, China
| | - Zhi-Pan Liu
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Key Laboratory for Computational Physical Sciences, Ministry of Education, Fudan University, Shanghai 200433, China, and School of Mathematical Sciences, Fudan University, Shanghai 200433, China
| | - LuLu Liu
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Key Laboratory for Computational Physical Sciences, Ministry of Education, Fudan University, Shanghai 200433, China, and School of Mathematical Sciences, Fudan University, Shanghai 200433, China
| | - Weiguo Gao
- Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials, Department of Chemistry, Key Laboratory for Computational Physical Sciences, Ministry of Education, Fudan University, Shanghai 200433, China, and School of Mathematical Sciences, Fudan University, Shanghai 200433, China
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206
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Juodkazis K, Juodkazyte J, Jelmakas E, Kalinauskas P, Valsiūnas I, Mecinskas P, Juodkazis S. Photoelectrolysis of water: Solar hydrogen--achievements and perspectives. OPTICS EXPRESS 2010; 18 Suppl 2:A147-A160. [PMID: 20588583 DOI: 10.1364/oe.18.00a147] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Thermodynamic analysis of energy conversion from light-to-chemical, light-to-electric and electric-to-chemical is presented by the case study of water photoelectrolysis on TiO(2) surface. It is demonstrated that at the current state-of-the-art energy conversion efficiency of water photoelectrolysis can be increased approximately 17 times by separating the processes of solar-to-electric and electric-to-chemical energy conversion and optimizing them independently. This allows to mitigate a high overvoltage of oxygen evolution reaction with respect to thermodynamic E(0)(O(2)/H(2)O) = 1.23 V potential as well as spectrally narrow absorbtivity of solar light by TiO(2) which determine the low efficiency (approximately 1.0%) of direct light-to-chemical energy conversion. Numerical estimates are provided illustrating practical principles for optimization of the solar energy conversion and storage processes.
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207
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Bui TD, Kimura A, Ikeda S, Matsumura M. Determination of Oxygen Sources for Oxidation of Benzene on TiO2 Photocatalysts in Aqueous Solutions Containing Molecular Oxygen. J Am Chem Soc 2010; 132:8453-8. [DOI: 10.1021/ja102305e] [Citation(s) in RCA: 128] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Thuan Duc Bui
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan, and Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
| | - Akira Kimura
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan, and Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
| | - Shigeru Ikeda
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan, and Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
| | - Michio Matsumura
- Research Center for Solar Energy Chemistry, Osaka University, 1-3 Machikaneyama, Toyonaka, Osaka 560-8531, Japan, and Institute of Materials Science, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi, Vietnam
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208
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Molecular Mechanism of Water Oxidation Reaction at Photo-Irradiated TiO 2 and Related Metal Oxide Surfaces. ACTA ACUST UNITED AC 2010. [DOI: 10.4028/www.scientific.net/ssp.162.1] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Recent studies on the molecular mechanism of water photooxidation (or oxygen photoevolution) reaction on TiO2 and related metal oxides or oxynitrides are reviewed. It is shown that a lot of experimental and theoretical studies give definite support to our recently proposed new mechanism, called “nucleophilic attack of H2O” or “Lewis acid-base” mechanism. The new mechanism has the prominent features that it possesses energetic and kinetics different from the conventional electron-transfer mechanism and can explain water photooxidation reaction on visible-light responsive metal oxides or oxynitrides, contrary to the conventional one. The result indicates that the new mechanism is useful for searching for new efficient visible-light responsive materials for solar water splitting.
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209
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Berger T, Rodes A, Gómez R. Oxalic acid photooxidation on rutile nanowire electrodes. Phys Chem Chem Phys 2010; 12:10503-11. [DOI: 10.1039/c003377d] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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210
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Chen CC, Wu RJ, Yao IC, Lu CS. Bis(2-chloroethoxy)methane degradation by TiO2 photocatalysis: parameter and reaction pathway investigations. JOURNAL OF HAZARDOUS MATERIALS 2009; 172:1021-1032. [PMID: 19720461 DOI: 10.1016/j.jhazmat.2009.07.093] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2009] [Revised: 07/22/2009] [Accepted: 07/22/2009] [Indexed: 05/28/2023]
Abstract
Haloethers are widely used in industry, and the release of these species into the environment is of great concern because of their toxicity and carcinogenicity. The present study deals with the photocatalytic degradation of the haloether, bis(2-chloroethoxy)methane (BCEXM), in the presence of TiO(2) particles and UV-A (lambda=365 nm) radiation. About 99.5% of BCEXM was degraded after UV irradiation for 16h. Factors such as solution pH, TiO(2) dosage, and the presence of anions were found to influence the degradation rate. To obtain a better understanding of the mechanistic details of this TiO(2)-assisted photodegradation of BCEXM with UV irradiation, the intermediates of the processes were separated, identified, and characterized by the solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) technique. To the best of our knowledge, this is the first report on the degradation pathways of BCEXM. The first step in the destruction of BCEXM is thought to be abstraction of a hydrogen by ()OH to form a carbon-centered radical which then reacts with O(2) to form a peroxyl radical. Peroxyl radicals react with one another and produce an alkoxy radical. The beta-bond fragmentation of the alkoxy radical produces different intermediates.
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Affiliation(s)
- Chiing-Chang Chen
- Department of Science Application and Dissemination, National Taichung University, Taichung 403, Taiwan, ROC
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211
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Kim D, Yang Y, Kim H, Berger A, Knez M, Gösele U, Schmidt V. Herstellung von Metalloxid-Nanoröhren in neutraler wässriger Lösung mithilfe des photokatalytischen Effektes. Angew Chem Int Ed Engl 2009. [DOI: 10.1002/ange.200903997] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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212
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Kim D, Yang Y, Kim H, Berger A, Knez M, Gösele U, Schmidt V. Formation of Metal Oxide Nanotubes in Neutral Aqueous Solution Based on a Photocatalytic Effect. Angew Chem Int Ed Engl 2009; 49:210-2. [DOI: 10.1002/anie.200903997] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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213
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Yang J, Dai J, Chen C, Zhao J. Effects of hydroxyl radicals and oxygen species on the 4-chlorophenol degradation by photoelectrocatalytic reactions with TiO2-film electrodes. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2009.08.007] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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214
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Li L, Liu CY. Facile Synthesis of Anatase-Brookite Mixed-Phase N-Doped TiO2Nanoparticles with High Visible-Light Photocatalytic Activity. Eur J Inorg Chem 2009. [DOI: 10.1002/ejic.200900369] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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215
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Wu Z, Sheng Z, Liu Y, Wang H, Tang N, Wang J. Characterization and activity of Pd-modified TiO2 catalysts for photocatalytic oxidation of NO in gas phase. JOURNAL OF HAZARDOUS MATERIALS 2009; 164:542-8. [PMID: 18823706 DOI: 10.1016/j.jhazmat.2008.08.028] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2008] [Revised: 08/12/2008] [Accepted: 08/12/2008] [Indexed: 05/23/2023]
Abstract
Pd-modified TiO(2) prepared by thermal impregnation method was used in this study for photocatalytic oxidation of NO in gas phase. The physico-chemical properties of Pd/TiO(2) catalysts were characterized by X-ray diffraction analysis (XRD), Brunauer-Emmett-Teller measurements (BET), X-ray photoelectron spectrum analysis (XPS), transmission electron microscopy (TEM), high resolution-transmission electron microscopy (HR-TEM), UV-vis diffuse reflectance spectra (UV-vis DRS) and photoluminescence spectra (PL). It was found that Pd dopant existed as PdO particles in as-prepared photocatalysts. The results of PL spectra indicated that the photogenerated electrons and holes were efficiently separated after Pd doping. During in situ XPS study, it was found that the content of hydroxyl groups on the surface of Pd/TiO(2) increased when the catalyst was irradiated by UV light, which could result in the improvement of photocatalytic activity. The activity test showed that the optimum Pd dopant content was 0.05 wt.%. And the maximum conversion of NO was about 72% higher than that of P25 when the initial concentration of NO was 200 ppm, which showed that Pd/TiO(2) photocatalysts could be potentially applied to oxidize higher concentration of NO.
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Affiliation(s)
- Zhongbiao Wu
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310027, PR China
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216
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Zhang D, Qiu R, Song L, Eric B, Mo Y, Huang X. Role of oxygen active species in the photocatalytic degradation of phenol using polymer sensitized TiO2 under visible light irradiation. JOURNAL OF HAZARDOUS MATERIALS 2009; 163:843-847. [PMID: 18718711 DOI: 10.1016/j.jhazmat.2008.07.036] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2008] [Revised: 07/07/2008] [Accepted: 07/08/2008] [Indexed: 05/26/2023]
Abstract
The role of dissolved oxygen, and of active species generated by photo-induced reactions with oxygen, in the photocatalytic degradation of phenol was investigated using polymer [poly-(fluorene-co-thiophene) with thiophene content of 30%, so-called PFT30] sensitized TiO2 (PFT30/TiO2) under visible light irradiation. The photoluminescent (PL) quantum yield of PFT30/TiO2 was about 30% of that of PFT30/Al(2)O(3), proving that electron transfer took place between the polymer and TiO2. The result that photocatalytic degradation of phenol was almost stopped when the solution was saturated with N(2) proved the importance of O(2). Addition of NaN(3), an effective quencher of singlet oxygen ((1)O(2)), caused about a 40% decrease in the phenol degradation ratio. Addition of alcohols caused about a 60% decrease in the phenol photodegradation ratio, indicating that the hydroxyl radicals (OH), whose presence was confirmed by electron spin resonance (ESR) spectroscopy, was the predominant active species in aqueous solution. In anhydrous solution, singlet oxygen ((1)O(2)) was the predominant species. These results indicate that oxygen plays a very important role in the photocatalytic degradation of phenol.
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Affiliation(s)
- Dongdong Zhang
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China
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217
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Bhattacharyya K, Varma S, Tripathi AK, Bharadwaj SR, Tyagi AK. Mechanistic Insight by in Situ FTIR for the Gas Phase Photo-oxidation of Ethylene by V-Doped Titania and Nano Titania. J Phys Chem B 2009; 113:5917-28. [DOI: 10.1021/jp8103529] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- K. Bhattacharyya
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400 085, India
| | - S. Varma
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400 085, India
| | - A. K. Tripathi
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400 085, India
| | - S. R. Bharadwaj
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400 085, India
| | - A. K. Tyagi
- Chemistry Division, Bhabha Atomic Research Centre, Mumbai-400 085, India
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218
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Valdés Á, Kroes GJ. First principles study of the photo-oxidation of water on tungsten trioxide (WO3). J Chem Phys 2009; 130:114701. [DOI: 10.1063/1.3088845] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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219
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Wu RJ, Chen CC, Chen MH, Lu CS. Titanium dioxide-mediated heterogeneous photocatalytic degradation of terbufos: parameter study and reaction pathways. JOURNAL OF HAZARDOUS MATERIALS 2009; 162:945-53. [PMID: 18599202 DOI: 10.1016/j.jhazmat.2008.05.121] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2008] [Revised: 05/24/2008] [Accepted: 05/26/2008] [Indexed: 05/23/2023]
Abstract
The photocatalytic degradation of terbufos in aqueous suspensions was investigated by using titanium dioxide (TiO(2)) as a photocatalyst. About 99% of terbufos was degraded after UV irradiation for 90 min. Factors such as pH of the system, TiO(2) dosage, and presence of anions were found to influence the degradation rate. Photodegradation of terbufos by TiO(2)/UV exhibited pseudo-first-order reaction kinetics, and a reaction quantum yield of 0.289. The electrical energy consumption per order of magnitude for photocatalytic degradation of terbufos was calculated and showed that a moderated efficiency (E(EO)=71 kWh/(m(3)order)) was obtained in TiO(2)/UV process. To obtain a better understanding of the mechanistic details of this TiO(2)-assisted photodegradation of terbufos with UV irradiation, the intermediates of the processes were separated, identified, and characterized by the solid-phase microextraction (SPME) and gas chromatography/mass spectrometry (GC/MS) technique. The probable photodegradation pathways were proposed and discussed.
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Affiliation(s)
- Ren-Jang Wu
- Department of Applied Chemistry, Providence University, Taichung 433, Taiwan
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220
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Shankar MV, Kako T, Wang D, Ye J. One-pot synthesis of peroxo-titania nanopowder and dual photochemical oxidation in aqueous methanol solution. J Colloid Interface Sci 2009; 331:132-7. [DOI: 10.1016/j.jcis.2008.11.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2008] [Revised: 11/10/2008] [Accepted: 11/11/2008] [Indexed: 10/21/2022]
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221
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Dimitrijevic NM, Rozhkova E, Rajh T. Dynamics of Localized Charges in Dopamine-Modified TiO2 and their Effect on the Formation of Reactive Oxygen Species. J Am Chem Soc 2009; 131:2893-9. [DOI: 10.1021/ja807654k] [Citation(s) in RCA: 139] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Nada M. Dimitrijevic
- Center for Nanoscale Materials, and Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Elena Rozhkova
- Center for Nanoscale Materials, and Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439
| | - Tijana Rajh
- Center for Nanoscale Materials, and Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439
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222
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Zou J, Gao J, Wang Y. Synthesis of highly active H2O2-sensitized sulfated titania nanoparticles with a response to visible light. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2008.12.001] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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223
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Liu G, Wang X, Chen Z, Cheng HM, Lu GQ(M. The role of crystal phase in determining photocatalytic activity of nitrogen doped TiO2. J Colloid Interface Sci 2009; 329:331-8. [DOI: 10.1016/j.jcis.2008.09.061] [Citation(s) in RCA: 95] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2008] [Accepted: 09/17/2008] [Indexed: 11/26/2022]
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224
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Chapter 1 Applications of Photoluminescence Spectroscopy to the Investigation of Oxide‐Containing Catalysts in the Working State. ADVANCES IN CATALYSIS 2009. [DOI: 10.1016/s0360-0564(08)00001-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
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225
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Photoelectrochemical Properties of BiVO4 Film Electrode in Alkaline Solution. CHINESE JOURNAL OF CATALYSIS 2008. [DOI: 10.1016/s1872-2067(08)60069-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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226
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Kohtani S, Yoshida K, Maekawa T, Iwase A, Kudo A, Miyabe H, Nakagaki R. Loading effects of silver oxides upon generation of reactive oxygen species in semiconductor photocatalysis. Phys Chem Chem Phys 2008; 10:2986-92. [DOI: 10.1039/b719913a] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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227
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Nelea V, Morosanu C, Bercu M, Mihailescu IN. Interfacial titanium oxide between hydroxyapatite and TiAlFe substrate. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2007; 18:2347-54. [PMID: 17569010 DOI: 10.1007/s10856-007-3135-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/20/2006] [Accepted: 07/28/2006] [Indexed: 05/15/2023]
Abstract
The interface between nano-crystalline hydroxyapatite (HA) thin films and a titanium alloy (Ti5Al2.5Fe) has been studied by means of Fourier transform infrared spectrophotometry and X-ray diffraction at grazing incidence. The HA thin films were deposited by radio-frequency magnetron sputtering in low pressure dry argon on substrates kept at low temperature or heated at 550 degrees C. The effect of film treatment by sputtering and annealing in humid air, as a simple, effective way of restoring the crystallinity and stoichiometry of the HA bulk, was studied in correlation with the development of a titanium oxide layer at the film-substrate interface. An interfacial TiO(2 )film grew at the interface during annealing in moist air, while a TiO(2) layer diffused into the HA films when directly sputtered at 550 degrees C. The formation of an interfacial titanium oxide layer was inhibited by the insertion of a crystalline TiN buffer interlayer between the substrate and the HA film. Separately, the mechanical characteristics of the different HA films were monitored by nanoindentation to find out how they had been affected.
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Affiliation(s)
- Valentin Nelea
- National Institute for Lasers, Plasma, and Radiation Physics, PO Box MG-54, Bucharest 77125, Romania
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228
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Filippone F, Mattioli G, Bonapasta AA. Reaction intermediates and pathways in the photoreduction of oxygen molecules at the (101) TiO2 (anatase) surface. Catal Today 2007. [DOI: 10.1016/j.cattod.2007.06.064] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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229
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The “Direct–Indirect” model: An alternative kinetic approach in heterogeneous photocatalysis based on the degree of interaction of dissolved pollutant species with the semiconductor surface. Catal Today 2007. [DOI: 10.1016/j.cattod.2007.08.002] [Citation(s) in RCA: 117] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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230
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Mattioli G, Filippone F, Amore Bonapasta A. Reaction intermediates in the photoreduction of oxygen molecules at the (101) TiO2 (anatase) surface. J Am Chem Soc 2007; 128:13772-80. [PMID: 17044705 DOI: 10.1021/ja062145x] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural, electronic, and vibrational properties of intermediates of the O(2) photoreduction at the (101) TiO(2) (anatase) surface have been investigated by performing ab initio density functional calculations. In detail, a recently proposed approach has been used where molecules on the surface are treated like surface defects. Thus, by applying theoretical methods generally used in the physics of semiconductors, we successfully estimate the location and donor/acceptor character of the electronic levels induced by an adsorbed molecule in the TiO(2) energy gap, both crucial for the surface-molecule charge-transfer processes, and investigate the formation and the properties of charged intermediates. The present approach permits a view of the O(2) photoreduction process through several facets, which elucidates the molecule-surface charge-transfer conditions and reveals the key role played by charged intermediates. A comparison of present results with those of a highly sensitive IR (infrared) spectroscopy study of intermediates of the O(2) photoreduction leads to a deeper understanding of this process and to revised vibrational-line assignments and reaction paths.
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Affiliation(s)
- Giuseppe Mattioli
- Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Via Salaria km 29.5, CP 10, I-00016 Monterotondo Stazione, Roma, Italy
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231
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Wang N, Chen Z, Zhu L, Jiang X, Lv B, Tang H. Synergistic effects of cupric and fluoride ions on photocatalytic degradation of phenol. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2007.04.023] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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232
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Hirakawa T, Daimon T, Kitazawa M, Ohguri N, Koga C, Negishi N, Matsuzawa S, Nosaka Y. An approach to estimating photocatalytic activity of TiO2 suspension by monitoring dissolved oxygen and superoxide ion on decomposing organic compounds. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2007.03.012] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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233
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Qu ZW, Kroes GJ. Theoretical study of the electronic structure and stability of titanium dioxide clusters (TiO2)n with n = 1-9. J Phys Chem B 2007; 110:8998-9007. [PMID: 16671707 DOI: 10.1021/jp056607p] [Citation(s) in RCA: 225] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electronic structure and the stability of both neutral and singly charged (TiO2)n clusters with n = 1-9 have been investigated using the density functional B3LYP/LANL2DZ method. The lowest-lying singlet clusters tend to form some compact structures with one or two terminal Ti-O bonds, which are about 1.4-2.5 eV more stable than the corresponding triplet structures. For the lowest-lying structures, strong infrared absorption lines at 988-1020 cm(-1) due to terminal Ti-O bonds and below 930 cm(-1) due to Ti-O-Ti bridging bonds may be observed, with some characteristic lines at 530-760 cm(-1) due to 3-fold coordinated O-atoms that are comparable with the spectra of rutile and anatase bulk. The holes and excited electrons within triplet structures tend to be localized on the least coordinated O- and Ti-atoms, respectively, with some exceptions possibly due to the electron-hole interaction. The extra electrons within (TiO2)n- clusters and the holes within (TiO2)n+ clusters show a clearer preference of location on the least coordinated Ti- and O-atoms, respectively. For the lowest-lying (TiO2)n clusters, the cluster formation energy per TiO2 unit and the electron affinity tend to increase whereas the ionization potential tends to decrease with the cluster size n. On the other hand, the singlet-triplet and HOMO-LUMO gaps represent the lower and upper limits of the TiO2 bulk band gaps, respectively. The theoretical results agree well with the available experimental data and may be helpful for understanding the chemistry of small (TiO2)n clusters.
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Affiliation(s)
- Zheng-Wang Qu
- Leiden Institute of Chemistry, Gorlaeus Laboratory, Leiden University P.O. Box 9502, 2300 RA Leiden, The Netherlands.
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234
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Chen CC, Lu CS. Mechanistic studies of the photocatalytic degradation of methyl green: an investigation of products of the decomposition processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2007; 41:4389-96. [PMID: 17626441 DOI: 10.1021/es062465g] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
The methyl green (MG) dye dissolves into an alkaline solution when the pH value is too high (pH 9). The cationic MG dye molecules are converted into the colorless carbinol base (CB) and produce crystal violet (CV) dye and ethanol by hydroxide anion. Thirty-three intermediates of the process were separated, identified, and characterized by HPLC-ESI-MS technique in this study and their evolution during the photocatalytic reaction is presented. Moreover, the other intermediates formed in the photocatalytic degradation MG processes were separated and identified by HPLC-PDA technique. The results indicated that the N-de-methylated degradation of CV dye took place in a stepwise manner to yield N-de-methylated CV species, and the N-de-alkylated degradation of CB also took place in a stepwise manner to yield N-de-alkylated CB species generated during the processes. Moreover, the oxidative degradation of the CV dye (or CB) occurs to yield 4-(N,N-dimethylamino)phenol (DAP), 4-(N,N-dimethylamino)-4'-(N',N'-dimethylamino)benzophenone (DDBP) and their N-de-methylated products [or to yield 4-(N-ethyl-N,N-dimethyl)aminophenol (EDAP), DDBP, 4-(N-ethyl-N,N-dimethylamino)-4'-(N',N'-dimethylamino)benzophenone (EDDBP), DAP, and their N-de-alkylated products], which were found for the first time. A proposed degradation pathway of CV and CB is presented, involving mainly the N-de-alkylation and oxidation reaction.
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Affiliation(s)
- Chiing-Chang Chen
- Department of General Education, National Taichung Nursing College, Taichung 403, Taiwan, ROC.
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235
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Nakamura R, Tanaka T, Nakato Y. Oxygen photoevolution on a tantalum oxynitride photocatalyst under visible-light irradiation: how does water photooxidation proceed on a metal-oxynitride surface? J Phys Chem B 2007; 109:8920-7. [PMID: 16852061 DOI: 10.1021/jp0501289] [Citation(s) in RCA: 94] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The mechanism of water photooxidation (oxygen photoevolution) on a TaON photocatalyst was studied on the basis of our previous studies on the mechanism of this reaction on TiO(2) and N-doped TiO(2). We have confirmed that photocatalytic O(2) evolution occurs from an aqueous TaON suspension in the presence of Fe(3+), as reported. In-situ MIR-IR experiments have indicated that the TaON surface is slightly oxidized under visible-light irradiation, indicating that the oxygen photoevolution on TaON actually occurs on a thin Ta-oxide overlayer. The in-situ MIR-IR experiments have also shown that a certain surface peroxo species, tentatively assigned to adsorbed HOOH, is formed as an intermediate of the O(2) photoevolution reaction. Studies on the effect of addition of reductants to the electrolyte on the IPCE have shown that photogenerated holes at the TaON surface cannot oxidize reductants such as SCN(-), Br(-), methanol, ethanol, 2-propanol, and acetic acid, though they can oxidize H(2)O into O(2). Detailed considerations of these results have strongly suggested that the water photooxidation reaction on TaON proceeds by our recently proposed new mechanism, that is, the reaction is initiated by a nucleophilic attack of a water molecule (Lewis base) on a surface-trapped hole (Lewis acid).
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Affiliation(s)
- Ryuhei Nakamura
- Division of Chemistry, Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
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236
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Lu CS, Chen CC, Mai FD, Wu YC. Photocatalytic degradation of Michler's Ethyl Ketone in titanium dioxide dispersions under UV irradiation. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2006.10.013] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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237
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Reaction of holes in nanocrystalline TiO2 films evaluated by highly sensitive transient absorption spectroscopy. Catal Today 2007. [DOI: 10.1016/j.cattod.2006.07.048] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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238
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Matsushita M, Tran TH, Nosaka AY, Nosaka Y. Photo-oxidation mechanism of l-alanine in TiO2 photocatalytic systems as studied by proton NMR spectroscopy. Catal Today 2007. [DOI: 10.1016/j.cattod.2006.07.046] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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239
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Qu ZW, Kroes GJ. Theoretical Study of Adsorption of O(3P) and H2O on the Rutile TiO2(110) Surface. J Phys Chem B 2006; 110:23306-14. [PMID: 17107180 DOI: 10.1021/jp065028x] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The adsorption of oxygen atoms O(3P) on both ideal and hydrated rutile TiO(2)(110) surfaces is investigated by periodic density functional theory (DFT) calculations within the revised Perdew-Burke-Ernzerhof (RPBE) generalized gradient approximation and a four Ti-layer slab, with (2 x 1) and (3 x 1) surface unit cells. It is shown that upon adsorption on the TiO(2) surface the spin of the O atom is completely lost, leading to stable surface peroxide species on both in-plane and bridging oxygen sites with O-binding energies of about 1.0-1.5 eV, rather than to the kinetically unstable terminal Ti-O and terminal O-O species with smaller binding energies of 0.1-0.7 eV. Changes in O-atom coverage ratios between 1/3 and 1 molecular layer (ML) and coadsorption of H(2)O have only minor effects on the O-binding energies of the stable peroxide configurations. High O-atom diffusion barriers of about 1 eV are found, suggesting a slow recombination rate of adsorbed O atoms on TiO(2)(110). Our results suggest that the TiOOTi peroxide intermediate experimentally observed in photoelectrolysis of water should be interpreted as a single spinless O adatom on TiO(2) surface rather than as two Ti-O* radicals coupled together.
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Affiliation(s)
- Zheng-Wang Qu
- Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, Post Office Box 9502, 2300 RA Leiden, The Netherlands.
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240
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Di Valentin C, Pacchioni G, Selloni A. Electronic structure of defect states in hydroxylated and reduced rutile TiO2(110) surfaces. PHYSICAL REVIEW LETTERS 2006; 97:166803. [PMID: 17155423 DOI: 10.1103/physrevlett.97.166803] [Citation(s) in RCA: 278] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/02/2006] [Revised: 08/01/2006] [Indexed: 05/12/2023]
Abstract
It has been experimentally observed that a bridging oxygen vacancy on the rutile TiO2(110) surface introduces localized Ti3+ 3d1 states about 1 eV below the conduction band which are not removed upon dissociation of a water molecule and formation of a pair of hydroxyl groups. Density functional calculations based on pure exchange-correlation functionals have not been able to satisfactorily reproduce and analyze these findings. Here we show that a correct description of the localized defect states on reduced and hydroxylated TiO2(110) is achieved only if proper geometry relaxation is accounted for using hybrid exchange functionals. We confirm the electron trapping nature of Ti(OH) groups but find no evidence that these defects should also act as hole traps by formation of Ti4+(OH)* radicals.
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Affiliation(s)
- Cristiana Di Valentin
- Dipartimento di Scienza dei Materiali, Università di Milano-Bicocca, Via R Cozzi 53, Milano, Italy
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241
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Thompson TL, Yates JT. Surface Science Studies of the Photoactivation of TiO2New Photochemical Processes. Chem Rev 2006; 106:4428-53. [PMID: 17031993 DOI: 10.1021/cr050172k] [Citation(s) in RCA: 920] [Impact Index Per Article: 51.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tracy L Thompson
- Surface Science Center, Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, USA
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242
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Murakami Y, Kenji E, Nosaka AY, Nosaka Y. Direct Detection of OH Radicals Diffused to the Gas Phase from the UV-Irradiated Photocatalytic TiO2 Surfaces by Means of Laser-Induced Fluorescence Spectroscopy. J Phys Chem B 2006; 110:16808-11. [PMID: 16927965 DOI: 10.1021/jp063293c] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The important roles of OH radicals for remote oxidation using TiO(2) photocatalysts were evidenced by the in situ detection of OH radicals in the gas phase using the laser-induced fluorescence (LIF) technique. The appearance of OD-LIF intensities after the exposure of D(2)O vapors over TiO(2) powders and the decrease of the time-resolved signals of OH-LIF intensities with increasing calcined temperatures of TiO(2) powders suggested that the exchangeable water at the TiO(2) surface is the origin of the diffused OH radicals.
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243
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Dolamic I, Bürgi T. Photoassisted Decomposition of Malonic Acid on TiO2 Studied by in Situ Attenuated Total Reflection Infrared Spectroscopy. J Phys Chem B 2006; 110:14898-904. [PMID: 16869601 DOI: 10.1021/jp0616967] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The photoassisted mineralization, i.e., conversion to CO2 and water, of malonic acid over P25 TiO2 was investigated by in situ attenuated total reflection infrared (ATR-IR) spectroscopy in a small volume flow-through cell. Reassignment of the vibrational bands of adsorbed malonic acid, assisted by deuterium labeling, reveals two dissimilar carboxylate groups within the molecule. This indicates adsorption via both carboxylate groups, one in a bridging or bidentate and the other in monodentate coordination. During irradiation the coverage of malonic acid strongly decreases, and oxalate is observed on the surface in at least two different adsorption modes. The major oxalate species observed during irradiation is characterized by monodentate coordination of both carboxylate groups. In the dark, however, part of these species adopts another adsorption mode, possibly interacting only with one carboxylate group. During band gap illumination a large fraction of the surface is not covered by acid. Oxalate is a major intermediate in the mineralization of malonic acid. However, the observed transient kinetics of adsorbed malonic and oxalic acid indicates additional pathways not involving oxalate. The rate constant for oxalate decomposition is slightly larger than the one for oxalate formation from malonic acid. As the oxalate is desorbing slowly from the surface its concentration in the liquid phase is small, despite the fact that it is a major intermediate in the mineralization of malonic acid.
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Affiliation(s)
- Igor Dolamic
- Université de Neuchâtel, Institut de Microtechnique, Rue Emile-Argand 11, 2009 Neuchâtel, Switzerland
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244
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Tachikawa T, Tojo S, Fujitsuka M, Majima T. One-Electron Redox Processes during Polyoxometalate-Mediated Photocatalytic Reactions of TiO2 Studied by Two-Color Two-Laser Flash Photolysis. Chemistry 2006; 12:3124-31. [PMID: 16358350 DOI: 10.1002/chem.200501077] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The one-electron redox processes of several compounds during polyoxometalate (POM)-mediated photocatalytic reactions of TiO(2) were investigated using the two-color two-laser flash-photolysis technique. The efficiency of the one-electron oxidation of aromatic sulfides by the trapped hole (h(tr) (+)) or the surface-bound OH radical (OH(s) (.)) is found to be significantly enhanced due to electron transfer from the conduction band (CB) of TiO(2) to the POM. The efficiency of the electron transfer from the CB of TiO(2) to the POM decreases in the order H(2)W(12)O(40) (6-) < SiW(12)O(40) (4-) < PW(12)O(40) (3-), that is, it depends on the reduction potential (E(red)) of the POMs. Electron injection from PW(12)O(40) (4-) in the excited state (PW(12)O(40) (4-*)) to the CB of TiO(2) was clearly observed using the two-color two-laser flash-photolysis technique. Storage of electrons in the TiO(2)/PW(12)O(40) (3-)/methyl viologen (MV(2+)) ternary system was also achieved upon two-color two-laser irradiation.
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Affiliation(s)
- Takashi Tachikawa
- The Institute of Scientific and Industrial Research (SANKEN), Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047, Japan
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245
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Probing of photocatalytic surface sites on SO42−/TiO2 solid acids by in situ FT-IR spectroscopy and pyridine adsorption. J Photochem Photobiol A Chem 2006. [DOI: 10.1016/j.jphotochem.2005.09.007] [Citation(s) in RCA: 162] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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246
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Fu H, Zhang L, Zhang S, Zhu Y, Zhao J. Electron Spin Resonance Spin-Trapping Detection of Radical Intermediates in N-Doped TiO2-Assisted Photodegradation of 4-Chlorophenol. J Phys Chem B 2006; 110:3061-5. [PMID: 16494309 DOI: 10.1021/jp055279q] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The electron spin resonance (ESR) spin-trapping technique using 5,5-dimethyl-1-pyrroline-N-oxide as the spin-trap reagent has been applied to detect free radical intermediates generated during in situ ultraviolet or visible irradiation of aqueous 4-chlorphenol (4-CP)/N-doped TiO(2) suspensions. ESR measurements gave the first direct evidence that the active species ((*)OH and O(2*-)) are responsible for the photodecomposition of 4-CP over N-doped TiO(2) under visible-light irradiation, strongly suggesting that the photocatalytic reaction of organic compounds in powdered N-doped TiO(2) systems proceed via surface intermediates of oxygen reduction or water oxidation, not via direct reaction with holes trapped at the N-induced midgap level. These results have important implications for the evaluation of the oxidative powder of TiO(2-x)N(x) catalysts.
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Affiliation(s)
- Hongbo Fu
- Department of Chemistry, Tsinghua University, Beijing 100084, China
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247
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Neumann B, Bogdanoff P, Tributsch H, Sakthivel S, Kisch H. Electrochemical Mass Spectroscopic and Surface Photovoltage Studies of Catalytic Water Photooxidation by Undoped and Carbon-Doped Titania. J Phys Chem B 2005; 109:16579-86. [PMID: 16853109 DOI: 10.1021/jp051339g] [Citation(s) in RCA: 141] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Carbon-doped TiO2, demonstrated as an efficient photocatalyst in visible light photooxidation of organic compounds, was prepared with different doping concentrations and investigated via differential electrochemical mass spectroscopy (DEMS) and capacitive surface photovoltage (SPV) measurements in the form of thin layer electrodes. In all cases the total photocurrent as well as the surface photovoltage of the doped materials decreased markedly in relation to the undoped one. No detectable oxygen evolved from the doped electrodes in acidic solution under UV-light excitation. Since an oxidation of formic acid is still apparent, it is concluded that this oxidation occurs via isolated, catalytically poorly active trap states within the forbidden energy region. The existence of these states is confirmed by capacitive SPV measurements.
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Affiliation(s)
- Bernhard Neumann
- Department Solare Energetik, Hahn-Meitner-Institut, Glienickerstrasse 100, D-14109 Berlin, Germany.
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248
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Yu ZT, Liao ZL, Jiang YS, Li GH, Chen JS. Water-Insoluble Ag-U-Organic Assemblies with Photocatalytic Activity. Chemistry 2005; 11:2642-50. [PMID: 15729678 DOI: 10.1002/chem.200401189] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Two metal-organic coordination polymers [Ag(bipy)(UO(2))(bdc)(1.5)] (bipy=2,2'-bipyridyl, bdc=1,4-benzenedicarboxylate) and [Ag(2)(phen)(2)UO(2)(btec)] (phen=1,10-phenanthroline, btec=1,2,4,5-benzenetetracarboxylate) were obtained by hydrothermal assembly of the d(10) metal silver and the 5f metal uranium with mixed ligands. Both compounds form two-dimensional networks with pi-pi overlap interactions between the aromatic fragments in the neighboring layers. In aqueous suspension the two water-insoluble materials show photocatalytic degradation performance superior to that of commercial TiO(2) (Degussa P-25) when tested on nonbiodegradable rhodamine B (RhB) as model pollutant. The relationship between the structure of the photocatalysts and the photocatalytic activity was also elucidated. On the basis of the monitored intermediate species and the final mineralized products, it is proposed that the possible reaction mechanism for the photodegradation (oxidation) of RhB in aqueous solution catalyzed by the two assembly compounds involves photoexcitation of uranyl centers and molecular oxygen.
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Affiliation(s)
- Zhen-Tao Yu
- State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun 130012, P. R. China
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249
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Nakamura R, Ohashi N, Imanishi A, Osawa T, Matsumoto Y, Koinuma H, Nakato Y. Crystal-Face Dependences of Surface Band Edges and Hole Reactivity, Revealed by Preparation of Essentially Atomically Smooth and Stable (110) and (100) n-TiO2 (Rutile) Surfaces. J Phys Chem B 2005; 109:1648-51. [PMID: 16851137 DOI: 10.1021/jp044710t] [Citation(s) in RCA: 104] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Essentially atomically smooth (100) and (110) n-TiO(2) (rutile) surfaces were prepared by immersion of commercially available single-crystal wafers in 20% HF, followed by annealing at 600 degrees C in air. The obtained surfaces were stable in aqueous solutions of pH 1-13, showing no change in the surface morphology on an atomic level, contrary to atomically flat surfaces prepared by ion sputtering and annealing under UHV. The success in preparation of the atomically smooth and stable n-TiO(2) surfaces enabled us to reveal clear crystal-face dependences of the surface band edges and hole reactivity in aqueous solutions.
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250
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Warren DS, McQuillan AJ. Influence of Adsorbed Water on Phonon and UV-Induced IR Absorptions of TiO2 Photocatalytic Particle Films. J Phys Chem B 2004. [DOI: 10.1021/jp0471812] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David S. Warren
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
| | - A. James McQuillan
- Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
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