Abstract
Titanium dioxide (TiO2)–silicon dioxide (SiO2) thin films were synthesized using the peroxo titanic acid approach (PTA) combined with the sol–gel method at low temperature around 100°C. The effects of type and amount of dopants of ferric (Fe3+) or thiourea (N-S) and co-dopants of Fe3+ and N-S on the films physicochemical properties and on the photocatalytic degradation of the methylene blue and formaldehyde under UV and visible light irradiation were investigated. Physicochemical properties of photocatalysts were characterized by X-ray diffraction, transmission electron microscopy, wavelength-dispersive X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and UV–Vis spectroscopy. The results showed that the TiO2 crystal phases obtained from this method were exclusively anatase and the needle-like crystals have an average diameter of 10–25 nm. Compared with the single dopant of 1.0 wt.% Fe3+ or 0.125 wt.% N-S that was the optimal concentration for photocatalytic degradation of methylene blue and formaldehyde, the co-dopants of 0.125 wt.% N-S + 1.0 wt.% Fe3+ furthermore increased the degradation efficiency. Co-dopants of 0.125 wt.% N-S + 1.0 wt.% Fe3+ in TiO2–SiO2 films were considered to play synergistic roles in narrowing TiO2 band gap resulting in the higher methylene blue and formaldehyde degradation efficiency. Since the crystal grain size of TiO2–SiO2 films synthesized by the PTA method is small, in the visible light region, the high transmittance was attainable to 80% with no-doped and dropped to 50–60% with doped thin films.
Similar content being viewed by others
References
Alemany, L. J., Banares, M. A., Pardo, E., Martin, F., Galán-Fereres, M., & Blasco, J. (1997). Photodegradation of phenol in water using silica-supported titania catalysts. Applied Catalysis B: Environmental, 13, 289–297.
Arconada, N., Durán, A., Suárez, S., Portela, R., Coronado, J. M., Sánchez, B., et al. (2009). Synthesis and photocatalytic properties of dense and porous TiO2-anatase thin films prepared by sol-gel. Applied Catalysis B: Environmental, 86, 1–7.
Asahi, R., Morikawa, T., Ohwaki, T., Aoki, K., & Taga, Y. (2001). Visible-light photocatalysis in nitrogen-doped titanium oxides. Science, 293, 269–271.
Barakat, M. A., Schaeffer, H., Hayes, G., & Ismat-Shah, S. (2005). Photocatalytic degradation of 2-chlorophenol by Co-doped TiO2 nanoparticles. Applied Catalysis B: Environmental, 57, 23–30.
Bockmeyer, M., Herbig, B., & Löbmann, P. (2009). Microstructure of sol-gel derived TiO2 thin films characterized by atmospheric ellipsometric porosimetry. Thin Solid Films, 517, 1596–1600.
Choi, W., Termin, A., & Hoffmann, M. R. (1994). The role of metal ion dopants in quantum-sized TiO2: correlation between photoreactivity and charge carrier recombination dynamics. The Journal of Physical Chemistry, 98, 13669–13679.
Deng, L., Chen, Y., Yao, M., Wang, S., Zhu, B., Huang, W., et al. (2010). Synthesis, characterization of B-doped TiO2 nanotubes with high photocatalytic activity. Journal of Sol-Gel Science and Technology, 53, 535–541.
Fan, C., Xue, P., & Sun, Y. (2006). Preparation of nano-TiO2 doped with cerium and its photocatalytic activity. Journal of Rare Earths, 24, 309–313.
Fujishima, A., Rao, T. N., & Tryk, D. A. (2000). Titanium dioxide photocatalysis. Journal of Photochemistry and Photobiology C: Photochemistry Reviews, 1, 1–21.
Ge, L., Xu, M. X., & Sun, M. (2006). Synthesis and characterization of TiO2 photocatalytic thin films prepared from refluxed PTA sols. Materials Letters, 60, 287–290.
Ghicov, A., Schmidt, B., Kunze, J., & Schmuki, P. (2007). Photoresponse in the visible range from Cr doped TiO2 nanotubes. Chemical Physics Letters, 433, 323–326.
Guo, B., Liu, Z., Hong, L., & Jiang, H. (2005). Sol gel derived photocatalytic porous TiO2 thin films. Surface and Coatings Technology, 198, 24–29.
Hao, H., & Zhang, J. (2009). The study of iron (III) and nitrogen co-doped mesoporous TiO2 photocatalysts: synthesis, characterization and activity. Microporous and Mesoporous Materials, 121, 52–57.
Huang, D., Liao, S., Quan, S., Liu, L., He, Z., Wan, J., et al. (2007). Preparation of anatase F doped TiO2 sol and its performance for photodegradation of formaldehyde. Journal of Materials Science, 42, 8193–8202.
Hung, W.-C., Fu, S.-H., Tseng, J.-J., Chu, H., & Ko, T.-H. (2007). Study on photocatalytic degradation of gaseous dichloromethane using pure and iron ion-doped TiO2 prepared by the sol-gel method. Chemosphere, 66, 2142–2151.
Ichinose, H., Terasaki, M., & Katsuki, H. (2001). Properties of peroxotitanium acid solution and peroxo-modified anatase sol derived from peroxotitanium hydrate. Journal of Sol-Gel Science and Technology, 22, 33–40.
Liu, W.-X., Ma, J., Qu, X.-G., & Cao, W.-B. (2009). Hydrothermal synthesis of (Fe, N) co-doped TiO2 powders and their photocatalytic properties under visible light irradiation. Research on Chemical Intermediates, 35, 321–328.
Liu, Z., Wang, Y., Chu, W., Li, Z., & Ge, C. (2010). Characteristics of doped TiO2 photocatalysts for the degradation of methylene blue waste water under visible light. Journal of Alloys and Compounds, 501, 54–59.
Ma, Y., Zhang, J., Tian, B., Chen, F., & Wang, L. (2010). Synthesis and characterization of thermally stable Sm, N co-doped TiO2 with highly visible light activity. Journal of Hazardous Materials, 182, 386–393.
Maggos, T., Bartzis, J. G., Liakou, M., & Gobin, C. (2007). Photocatalytic degradation of NOx gases using TiO2-containing paint: a real scale study. Journal of Hazardous Materials, 146, 668–673.
Meng, F., Song, X., & Sun, Z. (2009). Photocatalytic activity of TiO2 thin films deposited by RF magnetron sputtering. Vacuum, 83, 1147–1151.
Mo, J., Zhang, Y., Xu, Q., Lamson, J. J., & Zhao, R. (2009). Photocatalytic purification of volatile organic compounds in indoor air: a literature review. Atmospheric Environment, 43, 2229–2246.
Murashkevich, A., & Tsiulya, D. (2007). Preparation and investigation of composite SiO2-TiO2 films. Journal of Applied Spectroscopy, 74, 396–401.
Novotná, P., Zita, J., Krýsa, J., Kalousek, V., & Rathouský, J. (2008). Two-component transparent TiO2/SiO2 and TiO2/PDMS films as efficient photocatalysts for environmental cleaning. Applied Catalysis B: Environmental, 79, 179–185.
Obata, K., Irie, H., & Hashimoto, K. (2007). Enhanced photocatalytic activities of Ta, N co-doped TiO2 thin films under visible light. Chemical Physics, 339, 124–132.
Ohno, T., Miyamoto, Z., Nishijima, K., Kanemitsu, H., & Xueyuan, F. (2006). Sensitization of photocatalytic activity of S- or N-doped TiO2 particles by adsorbing Fe3+ cations. Applied Catalysis A: General, 302, 62–68.
Park, H., Jie, H., Chae, K.-H., Park, J.-K., Anpo, M., & Lee, D.-Y. (2008). Improvement of photocatalytic behavior of chemical-vapor-synthesized TiO2 nanopowders by post-heat treatment. Current Applied Physics, 8, 778–783.
Park, Y., Kim, W., Park, H., Tachikawa, T., Majima, T., & Choi, W. (2009). Carbon-doped TiO2 photocatalyst synthesized without using an external carbon precursor and the visible light activity. Applied Catalysis B: Environmental, 91, 355–361.
Photong, S., & Boonamnuayvitaya, V. (2009). Enhancement of formaldehyde degradation by amine functionalized silica/titania films. Journal of Environmental Sciences, 21, 1741–1746.
Photong, S., & Boonamnuayvitaya, V. (2010). Synthesis of APTMS-functionalized SiO2/TiO2 transparent film using peroxo titanic acid refluxed solution for formaldehyde removal. Water, Air, and Soil Pollution, 210, 453–461.
Pozzo, R. L., Giombi, J. L., Baltanás, M. A., & Cassano, A. E. (2000). The performance in a fluidized bed reactor of photocatalysts immobilized onto inert supports. Catalysis Today, 62, 175–187.
Rao, K. V. S., Lavédrine, B., & Boule, P. (2003). Influence of metallic species on TiO2 for the photocatalytic degradation of dyes and dye intermediates. Journal of Photochemistry and Photobiology A: Chemistry, 154, 189–193.
Ryu, Y. B., Lee, M. S., Jeong, E. D., Kim, H. G., Jung, W. Y., Baek, S. H., et al. (2007). Hydrothermal synthesis of titanium dioxides from peroxotitanate solution using different amine group-containing organics and their photocatalytic activity. Catalysis Today, 124, 88–93.
Sahoo, C., Gupta, A. K., & Pal, A. (2005). Photocatalytic degradation of methyl red dye in aqueous solutions under UV irradiation using Ag+ doped TiO2. Desalination, 181, 91–100.
Sasani Ghamsari, M., & Bahramian, A. R. (2008). High transparent sol-gel derived nanostructured TiO2 thin film. Materials Letters, 62, 361–364.
Socrates, G. (2001). Infrared and Raman characteristic group frequencies: tables and charts. England: Wiley.
Sonawane, R. S., & Dongare, M. K. (2006). Sol-gel synthesis of Au/TiO2 thin films for photocatalytic degradation of phenol in sunlight. Journal of Molecular Catalysis A: Chemical, 243, 68–76.
Sun, X., Liu, H., Dong, J., Wei, J., & Zhang, Y. (2010). Preparation and characterization of Ce/N-Codoped TiO2 particles for production of H2 by photocatalytic splitting water under visible light. Catalysis Letters, 135, 219–225.
Sung-Suh, H. M., Choi, J. R., Hah, H. J., Koo, S. M., & Bae, Y. C. (2004). Comparison of Ag deposition effects on the photocatalytic activity of nanoparticulate TiO2 under visible and UV light irradiation. Journal of Photochemistry and Photobiology A: Chemistry, 163, 37–44.
Tian, G., Pan, K., Fu, H., Jing, L., & Zhou, W. (2009). Enhanced photocatalytic activity of S-doped TiO2-ZrO2 nanoparticles under visible-light irradiation. Journal of Hazardous Materials, 166, 939–944.
Tong, T., Zhang, J., Tian, B., Chen, F., & He, D. (2008). Preparation of Fe3+-doped TiO2 catalysts by controlled hydrolysis of titanium alkoxide and study on their photocatalytic activity for methyl orange degradation. Journal of Hazardous Materials, 155, 572–579.
Ueda, M., Uchibayashi, Y., Otsuka-Yao-Matsuo, S., & Okura, T. (2008). Hydrothermal synthesis of anatase-type TiO2 films on Ti and Ti-Nb substrates. Journal of Alloys and Compounds, 459, 369–376.
Vogel, A. I. (1989). Vogel’s textbook of quantitive chemical analysis. New York: Wiley.
Wu, Y., Xing, M., Tian, B., Zhang, J., & Chen, F. (2010a). Preparation of nitrogen and fluorine co-doped mesoporous TiO2 microsphere and photodegradation of acid orange 7 under visible light. Chemical Engineering Journal, 162, 710–717.
Wu, Y., Zhang, J., Xiao, L., & Chen, F. (2010b). Properties of carbon and iron modified TiO2 photocatalyst synthesized at low temperature and photodegradation of acid orange 7 under visible light. Applied Surface Science, 256, 4260–4268.
Xie, Y., Li, Y., & Zhao, X. (2007a). Low-temperature preparation and visible-light-induced catalytic activity of anatase F-N-codoped TiO2. Journal of Molecular Catalysis A: Chemical, 277, 119–126.
Xie, Y., Zhao, Q., Zhao, X., & Li, Y. (2007b). Low temperature preparation and characterization of N-doped and N-S-codoped TiO2 by sol–gel route. Catalysis Letters, 118, 231–237.
Yamashita, H., Harada, M., Misaka, J., Takeuchi, M., Neppolian, B., & Anpo, M. (2003). Photocatalytic degradation of organic compounds diluted in water using visible light-responsive metal ion-implanted TiO2 catalysts: Fe ion-implanted TiO2. Catalysis Today, 84, 191–196.
Yang, W., & Wolden, C. A. (2006). Plasma-enhanced chemical vapor deposition of TiO2 thin films for dielectric applications. Thin Solid Films, 515, 1708–1713.
Yang, Y., Li, X.-J., Chen, J.-T., & Wang, L.-Y. (2004). Effect of doping mode on the photocatalytic activities of Mo/TiO2. Journal of Photochemistry and Photobiology A: Chemistry, 163, 517–522.
Yoon, K. H., Noh, J. S., Kwon, C. H., & Muhammed, M. (2006). Photocatalytic behavior of TiO2 thin films prepared by sol-gel process. Materials Chemistry and Physics, 95, 79–83.
Yu, J., Xiong, J., Cheng, B., & Liu, S. (2005). Fabrication and characterization of Ag-TiO2 multiphase nanocomposite thin films with enhanced photocatalytic activity. Applied Catalysis B: Environmental, 60, 211–221.
Yuan, Z., Zhang, J., Li, B., & Li, J. (2007). Effect of metal ion dopants on photochemical properties of anatase TiO2 films synthesized by a modified sol-gel method. Thin Solid Films, 515, 7091–7095.
Zhang, X., Zhou, M., & Lei, L. (2006). Co-deposition of photocatalytic Fe doped TiO2 coatings by MOCVD. Catalysis Communications, 7, 427–431.
Zhu, J., Chen, F., Zhang, J., Chen, H., & Anpo, M. (2006). Fe3+-TiO2 photocatalysts prepared by combining sol-gel method with hydrothermal treatment and their characterization. Journal of Photochemistry and Photobiology A: Chemistry, 180, 196–204.
Zielinska, A., Kowalska, E., Sobczak, J. W., Lacka, I., Gazda, M., Ohtani, B., et al. (2010). Silver-doped TiO2 prepared by microemulsion method: surface properties, bio- and photoactivity. Separation and Purification Technology, 72, 309–318.
Acknowledgments
This work was supported by the Royal Golden Jubilee Ph.D. Program, the Thai Research Fund (TRF), and the Higher Education Research Promotion and National Research University Project of Thailand, Office of the Higher Education Commission.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Kaewtip, C., Chadpunyanun, P. & Boonamnuayvitaya, V. Effect of Co-Dopants in TiO2–SiO2 Thin films on the Formaldehyde Degradation. Water Air Soil Pollut 223, 1455–1465 (2012). https://doi.org/10.1007/s11270-011-0957-8
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11270-011-0957-8