Tailoring the photocatalytic activity of nanoparticulate zinc oxide by transition metal oxide doping (original) (raw)
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Design and photocatalytic activity of nanosized zinc oxides
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This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. Highlights There is correlation between synthesis, structure and properties of nanoscaled ZnO's. The photocatalytic activity of ZnO under Vis radiation depends on its band gap level. The ZnO granulometry dominated its efficiency in AOP under UV radiation. Tribophysical treatment has a dual impact on the ZnO photocatalytic activity.
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Comparative study on photocatalytic activity of ZnO prepared by different methods
This article appeared in a journal published by Elsevier. The attached copy is furnished to the author for internal non-commercial research and education use, including for instruction at the authors institution and sharing with colleagues. Other uses, including reproduction and distribution, or selling or licensing copies, or posting to personal, institutional or third party websites are prohibited. In most cases authors are permitted to post their version of the article (e.g. in Word or Tex form) to their personal website or institutional repository. Authors requiring further information regarding Elsevier's archiving and manuscript policies are encouraged to visit: http://www.elsevier.com/authorsrights One of the best ways to reduce the contamination of water caused by the colored dyes used in the textile industries is photocatalytic treatment. The theme of the present investigation is photocatalytic degradation of organic dyes such as methylene blue and methyl orange in the presence of a catalyst like ZnO under UV light irradiation. The nanosized ZnO is prepared by three different methods namely sol–gel, precipitation and thermal decomposition method. The synthesized samples are calcinated at uniform temperature and are characterized by different techniques. Further, the efficiency of the catalyst and their photocatalytic mechanism are discussed in detail.
Applied Catalysis B: …, 2010
The aim of this study was to evaluate the effectiveness of using a range of innovative nanostructured high surface area zinc oxide (ZnO) thin films as photocatalysts, and thereafter to systematically relate initial and reacted surface morphology and irradiated surface area to photocatalytic activity under both limited and rich oxygen conditions. The thin films were produced using an innovative combination of magnetron sputtered surfaces and hydrothermal solution deposition that allows the morphology, porosity and thickness to be controlled by varying the composition and processing conditions. Methylene Blue (MB) was chosen as the model compound and the reaction was performed with ultra violet light (UV) at 254 nm. The thin film morphology and surface area before and after reaction was determined by scanning electron microscopy (SEM). The photocatalytic activity (measured as the rate and extent of MB degradation) was determined for seven different ZnO nanostructured thin films: three different ZnO hydrothermal solution depositions on bare glass slides (S1-CG, S2-CG and S3-CG films), the same three ZnO hydrothermal solution depositions but on glass slides coated with a magnetron sputtered ZnO film (S1-MS, S2-MS and S3-MS films), and glass slides coated with just a magnetron sputtered ZnO film (MS films).
Morphologies of zinc oxide particles and their effects on photocatalysis
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ZnO powders with different morphologies were synthesized by alkali precipitation, organo-zinc hydrolysis, and spray pyrolysis. Acetaldehyde decomposition was used as a probe reaction to evaluate the photocatalysis of these ZnO powders. We investigated the relationship between photocatalytic activity and crystallinity, surface area, or morphology. Results indicate that the photocatalytic activity of ZnO powder depends on crystallinity rather than surface area for the same original ZnO powders prepared by equal conditions other than the difference in calcination temperature. However, no direct relationship between photocatalytic activity and crystallinity or surface area was found for the differently original ZnO powders prepared by different methods, or the same method with different conditions. Instead, we find that the particle morphology significantly affects its photocatalysis.
Catalysis Today, 2019
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