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A Review on the Pathways of the Improved Structural Characteristics and Photocatalytic Performance of Titanium Dioxide (TiO2) Thin Films Fabricated by the Magnetron-Sputtering Technique. Catalysts 2020. [DOI: 10.3390/catal10060598] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Titanium dioxide (TiO2) thin films are used for a broad range of applications such as wastewater treatment, photocatalytic degradation activity, water splitting, antibacterial and also in biomedical applications. There is a wide range of synthesis techniques for the deposition of TiO2 thin films, such as chemical vapor deposition (CVD) and physical vapor deposition (PVD), both of which are well known deposition methods. Layer by layer deposition with good homogeneity, even thickness and good adhesive nature is possible by using the PVD technique, with the products being used for photocatalytic applications. This review studies the effects of magnetron sputtering conditions on TiO2 films. This innovative technique can enhance the photocatalytic activity by increasing the thickness of the film higher than any other methods. The main purpose of this article is to review the effects of DC and RF magnetron sputtering conditions on the preparation of TiO2 thin films for photocatalysis. The characteristics of TiO2 films (i.e., structure, composition, and crystallinity) are affected significantly by the substrate type, the sputtering power, the distance between substrate and target, working pressure, argon/oxygen ratio, deposition time, substrate temperature, dopant types, and finally the annealing treatment. The photocatalytic activity and optical properties, including the degree of crystallinity, band gap (Eg), refractive index (n), transmittance (T), and extinction coefficient (k), of TiO2 films are dependent on the above- mentioned film characteristics. Optimal TiO2 films should have a small particle size, a strong degree of crystallinity, a low band gap, a low contact angle, a high refractive index, transmittance, and extinction coefficient. Finally, metallic and nonmetallic dopants can be added to enhance the photocatalytic activity of TiO2 films by narrowing the band gap.
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Imani A, Oveisi H. 3D-Ordered Mesoporous Chromium-Doped Titania Thin Films: The Effect of Metal Dopant on the Microstructure, Mesoporous Symmetry, Hydrophobicity, and Surface Properties. ChemistrySelect 2018. [DOI: 10.1002/slct.201800149] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Amin Imani
- Department of Materials & Polymer Engineering; Hakim Sabzevari University; Sabzevar 9617976487 Iran
| | - Hamid Oveisi
- Department of Materials & Polymer Engineering; Hakim Sabzevari University; Sabzevar 9617976487 Iran
- International Centre for Theoretical Physics; Strada Costiera 11 34151 Trieste Italy
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Hui W, Guodong S, Xiaoshu Z, Wei Z, Lin H, Ying Y. In-situ synthesis of TiO 2 rutile/anatase heterostructure by DC magnetron sputtering at room temperature and thickness effect of outermost rutile layer on photocatalysis. J Environ Sci (China) 2017; 60:33-42. [PMID: 29031444 DOI: 10.1016/j.jes.2017.02.019] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 02/08/2017] [Accepted: 03/08/2017] [Indexed: 06/07/2023]
Abstract
TiO2 rutile/anatase heterostructure thin films with varying rutile thickness have been in-situ synthesized via DC magnetron sputtering with Ar gas at room temperature. The crystal texture, surface morphology, energy gap and optical properties of the films have been investigated by X-ray diffraction meter, grazing incidence X-ray diffraction meter, Raman spectroscopy, scanning electron microscopy, and UV-visible spectrophotometer, which indicates that the rutile/anatase heterostructure films are successfully fabricated. The further degradation experiments display that the photocatalytic activity can be dramatically affected by the thickness of the outmost rutile layer and the 100nm thickness exhibits the best performance in all of the TiO2 thin films. With the increase of the outmost rutile layer, the optical band gap of TiO2 film displays a systematic decrease slightly. However, the change in photocatalytic activity does not coincide with that in the band gap. The photoresponse and electrochemical properties of the thin films have been characterized to understand the mechanism of the varied photocatalytic activity.
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Affiliation(s)
- Wang Hui
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China; Hubei Province Key Laboratory of Systems Science in Metallurgical Process, Wuhan University of Science and Technology, Wuhan 430081, China.
| | - Shi Guodong
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China
| | - Zhang Xiaoshu
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China
| | - Zhang Wei
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China
| | - Huang Lin
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China
| | - Yu Ying
- College of Physical Science and Technology, Central China Normal University, Wuhan 430079, China.
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Twu M, Chiou A, Hu C, Hsu C, Kuo C. Properties of TiO2 films deposited on flexible substrates using direct current magnetron sputtering and using high power impulse magnetron sputtering. Polym Degrad Stab 2015. [DOI: 10.1016/j.polymdegradstab.2015.03.010] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Liu H, Yao T, Ding W, Wang H, Ju D, Chai W. Study on the optical property and surface morphology of N doped TiO₂ film deposited with different N₂ flow rates by DCPMS. J Environ Sci (China) 2013; 25 Suppl 1:S54-S58. [PMID: 25078840 DOI: 10.1016/s1001-0742(14)60626-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
N doped TiO2 films were deposited by direct current pulse magnetron sputtering system at room temperature. By using UV-Vis spectrophotometer and atomic force microscope, we studied the influence of N2 flow rate on the optical property and surface morphology of films. The results indicate that the optical property and surface morphology of N doped TiO2 film was dominated by the N2 flow rate. The mean absorbency in visible range of pure TiO2 films is near to 0%, which means that the pure TiO2 could hardly display the photocatalytic property in visible range. When N2 flow rate is 2 sccm, the mean absorbency in visible range of N doped TiO2 film could reach at 24%. In this case, the film could be used as photocatalyst induced by visible light. While with increasing N2 flow rate, the mean absorbency in visible range of N doped TiO2 film decreased abruptly. Especially when N2 flow rate exceeded 8 sccm, the mean absorbency in visible range of N doped TiO2 film decreased to about 0%, which is like pure TiO2 fimls.
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Affiliation(s)
- Honglin Liu
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China
| | - Tingting Yao
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China
| | - Wanyu Ding
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; Liaoning Province Education Department Engineering Research Center of Optoelectronic Materials and Device, Dalian 116028, China; Key Laboratory of Materials Modification by Laser, Ion and Electron Beams, Dalian University of Technology, Ministry of Education, Dalian 116028, China.
| | - Hualin Wang
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; Liaoning Province Education Department Engineering Research Center of Optoelectronic Materials and Device, Dalian 116028, China
| | - Dongying Ju
- Department of Material Science and Engineering, Saitama Institute of Technology, Fukaya 369-0293, Japan
| | - Weiping Chai
- School of Materials Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; Liaoning Province Education Department Engineering Research Center of Optoelectronic Materials and Device, Dalian 116028, China
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Ângelo J, Andrade L, Madeira LM, Mendes A. An overview of photocatalysis phenomena applied to NOx abatement. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2013; 129:522-39. [PMID: 24018117 DOI: 10.1016/j.jenvman.2013.08.006] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2013] [Revised: 07/02/2013] [Accepted: 08/01/2013] [Indexed: 05/22/2023]
Abstract
This review provides a short introduction to photocatalysis technology in terms of the present environmental remediation paradigm and, in particular, NOx photoabatement. The fundamentals of photoelectrochemical devices and the photocatalysis phenomena are reviewed, highlighting the main reaction mechanisms. The critical historical developments on heterogeneous photocatalysis are briefly discussed, giving particular emphasis to the pioneer works in this field. The third part of this work focus mainly on NOx removal technology considering topics such as: TiO2 photochemistry; effect of the operating conditions on the photocatalysis process; Langmuir-Hinshelwood modeling; TiO2 photocatalytic immobilization approaches; and their applications. The last section of the paper presents the main conclusions and perspectives on the opportunities related to this technology.
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Affiliation(s)
- Joana Ângelo
- LEPAE, Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Ding W, Ju D, Chai W. Composition and crystal structure of N doped TiO2 film deposited at different O2 flow rate by direct current sputtering. J Environ Sci (China) 2011; 23 Suppl:S119-S123. [PMID: 25084571 DOI: 10.1016/s1001-0742(11)61091-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
N doped Ti02 films were deposited by direct current pulse magnetron sputtering system at room temperature. The influence of 02 flow rate on the crystal structure of deposited films was studied by Stylus profilometer, X-ray photoelectron spectroscopy, and X-ray diffractometer. The results indicate that the 02 flow rate strongly controls the growth behavior and crystal structure of N doped Ti02 film. It is found that N element mainly exists as substitutional doped state and the chemical stiochiometry is near to TiO1.68±0.06N0.11±0.01 for all film samples. N doped Ti02 film deposited with 2 sccm (standard-state cubic centimeter per minute) 02 flow rate is amorphous structure with high growth rate, which contains both anatase phase and rutile phase crystal nucleuses. In this case, the film displays the mix-phase of anatase and rutile after annealing treatment. While N doped Ti02 film deposited with 12 cm(3)/min 02 flow rate displays anatase phase before and after annealing treatment. And it should be noticed that no TiN phase appears for all samples before and after annealing treatment.
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Affiliation(s)
- Wanyu Ding
- School of Material Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; Engineering Research Center of Optoelectronic Materials & Devices, Education Department of Liaoning Province, Dalian 116028, China; Key Laboratory of Materials Modification by Laser, Ion and Electron Beams (Dalian University of Technology), Ministry of Education, Dalian 116024, China
| | - Dongying Ju
- Department of Material Science and Engineering, Saitama Institute of Technology, Fukaya 369-0293, Japan
| | - Weiping Chai
- School of Material Science and Engineering, Dalian Jiaotong University, Dalian 116028, China; Engineering Research Center of Optoelectronic Materials & Devices, Education Department of Liaoning Province, Dalian 116028, China
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Wu D, You H, Du J, Chen C, Jin D. Effects of UV/Ag-TiO2/O3 advanced oxidation on unicellular green alga Dunaliella salina: implications for removal of invasive species from ballast water. J Environ Sci (China) 2011; 23:513-519. [PMID: 21520822 DOI: 10.1016/s1001-0742(10)60443-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The UV/Ag-TiO2/O3 process was investigated for ballast water treatment using Dunaliella salina as an indicator. Inactivation curves were obtained, and the toxicity of effluent was determined. Compared with individual unit processes using ozone or UV/Ag-TiO2, the inactivation efficiency of D. salina by the combined UV/Ag-TiO2/O3 process was enhanced. The presence of ozone caused an immediate decrease in chlorophyll a (chl-a) concentration. Inactivation efficiency and ch1-a removal efficiency were positively correlated with ozone dose and ultraviolet intensity. The initial total residual oxidant (TRO) concentration of effluent increased with increasing ozone dose, and persistence of TRO resulted in an extended period of toxicity. The results suggest that UV/Ag-TiO2/O3 has potential for ballast water treatment.
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Affiliation(s)
- Donghai Wu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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