SYNTHESIS AND CHARACTERISATION OF W–, Ag–, AND W/Ag– CO-DOPED TITANIA NANOPOWDERS, AND THEIR PHOTOCATALYTIC ACTIVITY
Keywords:
Sol-gel synthesis, nanostructures, X-ray diffraction, optical properties, doped titania, photocatalysisAbstract
Tungsten, silver, and tungsten/silver co-doped titaniananopowders were synthesised via an aqueous sol-gel method. The dried gels were thermally treated at 2 different temperatures, and the occurrence of the amorphous phase was assessed, using the combined Rietveld-RIR method, on the X-ray powder diffraction data. Systematic studies of the crystal structure and of the optical properties of the powders – made with diffuse reflectance spectroscopy (DRS) – were performed. The energy band gap was calculated using the differential reflectance method; their morphology was investigated using field emission scanning electron microscopy and transmission electron microscopy analyses (FE-SEM and TEM, respectively). The photocatalytic activity of the samples was assessed in liquid-solid phase, under UVA-light and visible-light irradiation, monitoring the degradation of an organic dye. The influence of the phase composition, optical properties, dimensions, and specific surface area of the powders on the photocatalytic activity was thoroughly discussed.
References
Al-Ekabi, H. and Serpone, N. (1988). Kinetics studies in heterogeneous photocatalysis. I. Photocatalytic degradation of chlorinated phenols in aerated aqueous solutions over titania supported on a glass matrix. J. Phys. Chem.-US, 92:5,726-5,731.
Arsac, F., Bianchi, D., Chovelon, J.M., Conchon, P., Ferronato, C., Lair,A., andSleiman, M. (2008). Photocatalytic degradation of organic pollutants in water and in air. An analytical approach. Mater. Sci. Eng. C, 28:722-725.
Augustynski, J. (1993). The role of the surface intermediates in the photoelectrochemical behaviour of anatase and rutile TiO2. Electrochim. Acta, 38:43-46.
Chao, H.E., Yun, Y.U., Xingfang, H.U., and Larbot, A. (2003). Effect of silver doping on the phase transformation and grain growth of sol-gel titania powder. J. Eur. Ceram. Soc., 23:1457-1464.
Chen, J. and Poon, C.-S. (2009). Photocatalytic construction and building materials: from fundamentals to applications. Build. Environ., 44:1899-1906.
Choi, W., Termin, A., and Hoffmann, M.R. (1994). The role of metal ion dopants in quantum-sized TiO2: correlation between photoreactivity and charge carrier recombination dynamics. J. Phys. Chem., 98:13669-13679.
Di Paola, A., García-López, E., Ikeda, S., Marcì, G., Ohtani, B., í and Palmisano, L. (2002). Photocatalytic degradation of organic compounds in aqueous systems by transition metal doped polycrystalline TiO2. Catal. Today,75:87-93.
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. J. Phys. Chem. B,104:4815-4820.
Dubrovinsky, L.S., Dubrovinskaia, N.A., Swamy, V., Muscat, J., Harrison, N.M., Ahuja, R., Holm, B., and Johansson, B. (2001). Materials science. The hardest known oxide. Nature, 410:653-654.
Fuerte, A., Hernández-Alonso, M.D., Maira, A.J., Martínez-Arias, A., Fernández-García, M., Conesa, J.C., and Soria, J. (2001). Visible light-activated nanosized doped-TiO2 photocatalyst. Chem. Commun., 24:2718-2719.
Fujishima, A. and Honda, K. (1972). Electrochemical photolysis of water at a semiconductor electrode. Nature, 238:37-38.
Fujishima, A., Hashimoto, K., and Watanabe, T. (1999). TiO2 Photocatalysis: Fundamentals and Applications. BKC, Inc., Tokyo, Japan, 126p.
Fujishima, A., Rao, T.N., and Trick, D.A. (2000). Titanium dioxide photocatalysis. J. Photochem. Photobiol. C, , 1:1-21.
García-Serrano, J., Gómez-Hernández, E., Ocampo-Fernández, M., and Pal, U. (2009) Effect of Agdoping on the crystallization and phase transition of TiO2 nanoparticles. Curr. Appl. Phys., 9:1097-1105.
Gualtieri A.F. and Brignoli, G. (2004). Rapid and accurate quantitative phase analysis using a fast detector. J. Appl. Crystallogr., 37:8-13.
Gualtieri, A.F. (2000). Accuracy of XRPD QPA using the combined Rietveld – RIR method. J. Appl. Crystallogr., 33:267-278.
Guo, M. and Du, J. (2012). First-principles study of electronic structures and optical properties of Cu, Ag, and Au-doped anatase TiO2. Physica B, 407:1003-1007.
Haines, J. and Leger, J.M. (1993). X-ray diffraction study of TiO2 up to 49 GPa. Physica B, 192:233-237.
Herrmann, J.-M., Duchamp, C., Karkmaz, M., Hoai, B.T., Lachheb, H., Puzenat, E., and Guillard, C. (2007). Environmental green chemistry as defined by photocatalysis. J. Hazard. Mater.,146:624-629.
Hoffmann, M.R., Martin, S.T., Choi, W., and Bahnemann, D.W. (1995). Environmental applications of semiconductor photocatalysis. Chem. Rev., 95:69-96.
Howard, C.J., Sabine,T.M., and Dickson, F. (1991). Structural and thermal parameters for rutile and anatase. ActaCrystallogr., B47:462-468.
Hutter, E., Fendler, J.H., and Roy, D. (2001). Surface plasmon resonance studies of gold and silver nanoparticles linked to gold and silver substrates by 2-aminoethanethiol and 1,6-hexanedithiol. J. Phys. Chem. B,105:11159-11168.
Jana, N.R., Sau, T.K., and Pal, T. (1999). Growing small silver particle as redox catalyst. J. Phys.Chem. B, 103:115-121.
Jin, R., Cao, Y.C., Hao, H., M?traux, G.S., Schatz, G.C., and Mirkin, C.A. (2003). Controlling anisotropic nanoparticle growth through plasmon excitation. Nature, 425:487-490.
Karvinen, S. and Lamminmäki, R-J. (2003). Preparation and characterization of mesoporous visible-light-active anatase. SolidState Sci., 5:1159-1166.
Kominami, H., Murakami, S., Kato, J., Kera, Y., and Ohtani, B. (2002). Correlation between some physical properties of titanium dioxide particles and their photocatalytic activity for some probe reactions in aqueous systems.J. Phys. Chem. B, 106:10501-10507.
Komornicki, S., Radecka, M., and Sobaś, P. (2004). Structural, electrical and optical properties of TiO2–WO3 polycrystalline ceramics. Mater. Res. Bull., 39:2007-2017.
Kwon, Y.T., Song, K.Y., Lee, W.I., Choi, G.J., and Do, Y.R. (2000). Photocatalytic behaviour of WO3-loaded TiO2 in an oxidation reaction. J. Catal., 191:192-199.
Lansdown, A.B.G. (2010). Silver in Healthcare: ItsAntimicrobial Efficacy and Safety in Use. 1st ed. Royal Society of Chemistry, Cambridge, UK, 280p.
Larson,A.C. and Von Dreele, R.B. (2000). General Structure Analysis System (GSAS). Los Alamos National Laboratory Report LAUR 86-784, Los Alamos, NM, USA.
Li,X.Z., Li, F.B., Yang, C.L., and Ge, W.K. (2001). Photocatalytic activity of WOx-TiO2 undervisible light irradiation, J. Photoch. Photobio. A, 141:209-217.
Malato, S., Fernández-Ibáñez, P., Maldonado, M.I., Blanco, J., and Gernjak, W. (2009). Decontamination and disinfection of water by solar photocatalysis: recent overview and trends. Catal. Today,147:1-59.
Marfunin, A.S. (1979). Physics of Minerals and Inorganic Materials. An Introduction, Springer-Verlag, Berlin, Germany, 340p.
Meagher, E.P. and Lager, G.A. (1979). Polyhedral thermal expansion in the TiO2 polymorphs: refinement of the crystal structures of rutile and brookite at high temperature. Can. Mineral., 17:77-85.
Muscat, J. Swamy, V., and Harrison, N.M. (2002). First-principles calculations of the phase stability of TiO2. Phys. Rev. B, 65:224112
Ohno,T., Sarukawa, K., and Matsumura, M. (2001). Photocatalytic activities of pure rutile particles isolated from TiO2 powder by dissolving the anatase component in HF solution. J. Phys. Chem. B, 105:2417-2420.
Okada, K., Yamamoto, N., Kameshima, Y., Yasumori, A., and Mac Kenzie, K.J.D. (2001). Effect of silica additive on the anatase-to-rutile phase transition, J. Am. Ceram. Soc., 84:1591-1596.
O’Regan, B. and Grätzel, M. (1991). A low-cost, high-efficiency solar cell based on dye-sensitized colloidal TiO2 films. Nature, 353:737-749.
Pan, H., Qiu, X., Ivanov, I.N., Meyer, H.M., Wang, W., Zhu,W., Parans Paranthaman, M., Zhang, Z., Eres,G., and Gu, B. (2009). Fabrication andcharacterization of brookite-rich, visible light-active TiO2 films for water splitting. Appl. Catal. B-Environ., 93:90-95.
Puddu, V., Choi, H., Dionysiou, D.D., and Li Puma G. (2010). TiO2 photocatalyst for indoor air remediation: influence of crystallinity, crystal phase, and UV radiation intensity on trichloroethylene degradation. Appl. Catal.B-Environ., 94:211-218.
Sakthivel, S., Shankar, M.V., Palanichamy, M., Banumathi, A., Bahnemann, D.W., and Murugesan, V. (2004). Enhancement of photocatalytic activity by metal deposition: characterisation and photonic efficiency ofPt, Au and Pd deposited on TiO2 catalyst.Water Res., 38:3001-3008.
Sato, H., Endo, S., Sugiyama, M., Kikegawa, T., Shimomura, 0., and Kusaba, K. (1991) Baddeleyite-type high-pressure phase of TiO2. Science, 251: 786-788.
Sclafani, A. and Herrmann, J-M. (1998). Influence of metallic silver and of platinum-silver bimetallic deposits on the photocatalytic activity of titania (anatase and rutile) in organic and aqueous media. J. Photoch. Photobio. A, 113:181-188.
Serpone, N., Lawless, D., Disdier, J., and Herrmann,J-M. (1994) Spectroscopic, photoconductivity, and photocatalytic studies of TiO2 colloids: naked and with the lattice doped with Cr3+, Fe3+, and V5+ cations. Langmuir,10:643-652.
Shannon, R.D. (1976). Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr., A32:751-767.
Tatsuma, T., Saitoh, S., Ohko,Y., and Fujishima, A. (2001). TiO2–WO3 photoelectrochemical anticorrosion system with an energy storage ability. Chem. Mater., 13:2838-2842.
Tobaldi, D.M., Tucci, A., Sever Škapin, A., and Esposito, L. (2010). Effects of SiO2 addition on TiO2 crystal structure and photocatalytic activity. J. Eur. Ceram. Soc., 30:2,481-2,490.
Toby, B.H. (2001). EXPGUI, a graphical user interface for GSAS. J Appl. Crystallogr., 34:210-213.
Wang, Y. and Herron, N. (1991). Nanometer-sized semiconductor clusters: materials synthesis, quantum size effects, and photophysical properties. J. Phys. Chem., 95:525-532.
Weir, A., Westerhoff, P., Fabricius, L., Hristovski, K., and von Goetz, N. (2012). Titanium dioxide nanoparticles in food and personal care products. Environ. Sci. Technol., 46:2242-2250.
Xu, H. and Zhang, L. (2009). Controllable one-pot synthesis and enhanced photocatalyticactivity of mixed-phase TiO2 nanocrystals with tunablebrookite/rutile ratios. J. Phys. Chem. C, 113:1785-1790.
Yin, S., Hasegawa, H., Maeda, D., Ishitsuka, M., and Sato,T. (2004). Synthesis of visible-light-active nanosize rutile titaniaphotocatalyst by low temperature dissolution–reprecipitation process. J. Photoch. Photobio. A, 163:1-8.
Zhang, H. and Banfield, J.F. (2000). Understanding polymorphic phase transformation ehaviourduring growth of nanocrystallineaggregates:insights from TiO2, J.Phys. Chem. B, 104: 3481-3487.
