Semiconductor-based photocatalysts have been extensively studied for oxidative photodestruction of organic pollutants in wastewaters, releasing non-toxic substances such as Azo dyes. Various synthesized catalyst specimens were characterized to determine the correlation between preparation conditions (catalyst type, dopant, microstructure, preparation routs, optical and physico-chemical properties) on the photocatalytic activity. Some researchers focused on the process parameters to optimize them to reach higher photoactivity. The specific surface areas, crystalline size, charge and pretreatment of the surface have significant effects on the physical and photocatalytic properties of the semiconductors. The surface sites of catalyst (TiO2) were modified by doping ZnS nanoparticles in the form of Core-Shell structure and the photocatalytic activities were determined by using color degradation and hydrogen production tests. The dye adsorption isotherms of photocatalyst were determined using UV-Vis spectroscopy. The specific surface properties were determined from BET, Zeta meter and Particle size analyzer tests. Photocatalytic decolorization of AR and water splitting test were applied to understand the relation between the surface properties and the photocatalytic activity. The result indicated that core-shell prepared samples had different surface suitable sites to cooperate in photocatalytic reaction.
References
[1]
Hoffmann, M.R., et al. (1995) Environmental Applications of Semiconductor Photocatalysis. Chemical Reviews, 95, 69-96. https://doi.org/10.1021/cr00033a004
[2]
Kudo, A. (2006) Development of Photocatalyst Materials for Water Splitting. International Journal of Hydrogen Energy, 31, 197-202. https://doi.org/10.1016/j.ijhydene.2005.04.050
[3]
Fujishima, A., Zhang, X.T. and Tryk, D.A. (2008) TiO2 Photocatalysis and Related Surface Phenomena. Surface Science Reports, 63, 515-582. https://doi.org/10.1016/j.surfrep.2008.10.001
[4]
Diebold, U. (2003) The Surface Science of Titanium Dioxide. Surface Science Reports, 48, 53-229. https://doi.org/10.1016/S0167-5729(02)00100-0
[5]
Caruso, F. (2001) Nanoengineering of Particle Surfaces. Advanced Materials, 13, 11-22. https://doi.org/10.1002/1521-4095(200101)13:1<11::AID-ADMA11>3.0.CO;2-N
[6]
Cushing, B.L., Kolesnichenko, V.L. and O’Connor, C.J. (2004) Recent Advances in the Liquid-Phase Syntheses of Inorganic Nanoparticles. Chemical Reviews, 104, 3893-3946. https://doi.org/10.1021/cr030027b
[7]
Bawendi, M.G., et al. (1997) (CdSe)ZnS Core-Shell Quantum Dots: Synthesis and Characterization of a Size Series of Highly Luminescent Nanocrystallites. The Journal of Physical Chemistry B, 101, 9463-9475. https://doi.org/10.1021/jp971091y
[8]
Peng, T.Y., Hasegawa, A., Qiu, J.R. and Hirao, K. (2003) Fabrication of Titania Tubules with High Surface Area and Well-Developed Mesostructural Walls by Surfactant-Mediated Templating Method. Chemistry of Materials, 15, 2011-2016. https://doi.org/10.1021/cm020828f
[9]
Kim, S., Fisher, B., Eisler, H.-J. and Bawendi, M. (2003) Type-II Quantum Dots: CdTe/CdSe(Core/Shell) and CdSe/ZnTe(Core/Shell) Heterostructures. Journal of the American Chemical Society, 125, 11466-11467. https://doi.org/10.1021/ja0361749
[10]
Kolenko, Y.V., Maximov, V.D., Garshev, A.V., Meskin, P.E., Oleynikov, N.N. and Churagulov, B.R. (2004) Hydrothermal Synthesis of Nanocrystalline and Mesoporous Titania from Aqueous Complex Titanyl Oxalate Acid Solutions. Chemical Physics Letters, 388, 411-415. https://doi.org/10.1016/j.cplett.2004.03.042
[11]
Fang, X.S., Zhai, T.Y., Gautam, U.K., Li, L., Wu, L.M., Bando, Y. and Golberg, D. (2011) ZnS Nanostructures: From Synthesis to Applications. Progress in Materials Science, 56, 175-287. https://doi.org/10.1016/j.pmatsci.2010.10.001
[12]
Perumal, S. (2015) Photocatalytic Studies of Anatase and Rutile Phase TiO2 Nanocrystals Prepared via Solvothermal Method. International Journal of Engineering Research and Applications, 5, 115-118.
[13]
Daneshvar, N., Salari, D. and Khataee, A.R. (2004) Photocatalytic Degradation of Azo Dye Acid Red 14 in Water on ZnO as an Alternative Catalyst to TiO2. Journal of Photochemistry and Photobiology A: Chemistry, 162, 317-322. https://doi.org/10.1016/S1010-6030(03)00378-2
[14]
Chatterjee, D. and Dasgupta, S. (2005) Visible Light Induced Photocatalytic Degradation of Organic Pollutants. Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 6, 186-205. https://doi.org/10.1016/j.jphotochemrev.2005.09.001
[15]
Crini, G. (2006) Non-Conventional Low-Cost Adsorbents for Dye Removal: A Review. Bioresource Technology, 97, 1061-1085. https://doi.org/10.1016/j.biortech.2005.05.001
[16]
Gong, S., Yao, D., Feng, X. and Jiang, H. (2006) Quantum Size Dependent Optical Nutation in a Core-Shell CdSe/ZnS Quantum Dot. Microelectronics Journal, 37, 904-909. https://doi.org/10.1016/j.mejo.2006.01.015
[17]
Ding, Z., Lu, G.Q. and Greenfield, P.F. (2000) Role of the Crystallite Phase of TiO2 in Heterogeneous Photocatalysis for Phenol Oxidation in Water. The Journal of Physical Chemistry B, 104, 4815-4820. https://doi.org/10.1021/jp993819b
