Preparation, characterization and photocatalytic activity of TiO2 / Methylcellulose nanocomposite films derived from nanopowder TiO2 and modified sol–gel titania
TiO2—methylcellulose (MC) nanocomposite films processed by the sol-gel technique were studied for phocatalytic applications. Precalcined TiO2 nanopowder was mixed with a sol and heat treated. The sol suspension was prepared by first adding titanium tetra isopropoxide (Ti(OPr)4 or TTP) to a mixture of ethanol and HCl (molar ratio TTP:HCl:EtOH:H2O = 1:1.1:10:10) and then adding a 2 wt.% solution of methylcellulose (MC). The TiO2 nanopowder was dispersed in the sol and the mixture was deposited on a microscope glass slide by spin coating. Problems of film inhomogeneity and defects which caused peeling and cracking during calcinations, because of film shrinkage, were overcome by using MC as a dispersant. Effect of MC on the structure evaluation, crystallization behavior and mechanical integrity with thermal treatment up to 500 °C are followed by SEM, XRD and scratch test. XRD Scanning electron microscopy (SEM) showed that the composite films with MC have much rougher surface than films made without MC. Composite films heat treated at approximately 500 °C have the greatest hardness values. For the composite thick film, the minimum load which caused the complete coating removal was 200 g/mm2, an indication of a strong bond to the substrate. Photocatalytic activities of the composite film were evaluated through the degradation of a model pollutant, the textile dye, Light Yellow X6G (C.I. Reactive Yellow 2) and were compared with the activity of (i) a similar composite film without MC, and (ii) a TiO2 nanopowder. The good mechanical integrity make this composite film an interesting candidate for practical catalytic applications.
KeywordsTiO2 Photocatalytic Activity Composite Film TiO2 Film Methylcellulose
The authors wish to thank the University of Isfahan for financially supporting this work. We wish to thank Kermanshah Oil Refinery for their partial support.
- 3.Maguire RJ (1992) Water Sci Technol 25:265Google Scholar
- 5.Chudgar RJ (1991) In: Kroschwits JI, Howe-Grant M (Eds) Kirk-Othmer encyclopedia of chemical technology, vol. 3. John Wiley & Sons Inc, New YorkGoogle Scholar
- 9.Ollis DF, Al-Ekabi H (eds) (1993) Photocatalytic purification and treatment of water and air. Elsevier Science Publishers, AmsterdamGoogle Scholar
- 19.Chan CK, Porter JF, Li YG, Guo W, Chan CM (1999) J Am Ceram Soc 83:566Google Scholar
- 22.Woolfrey JL, Bartlett JR (1998) In: Klein LC, Pope EJA, Sakka S, Woolfrey JL (eds) Sol–gel processing of advanced materials. The American Ceramic Society, p 3Google Scholar
- 23.Mackenzie JD (1986) In: Hench LL, Urlich DR (eds) Science of ceramic chemical processing, WileyGoogle Scholar
- 25.Bouquin O, Blanchard N, Colombian PH (1987) In: Vincenzini P (ed) High tech ceramics. Elsevier, AmsterdamGoogle Scholar
- 27.Brinker CJ, Scherer GW (1990) Sol–gel science – the physics and chemistry of sol–gel processing. Academic PressGoogle Scholar
- 30.Ring TA (1996) Fundamentals of ceramic powder processing and synthesis. Academic PressGoogle Scholar
- 31.German RM (1996) Sintering theory and practice. Wiley, New York, p.67Google Scholar
- 39.Habibi MH, Talebian N (2005) Acta Chim Slov 52:53Google Scholar
- 40.Hassanzadeh A, Habibi MH, Zeini Isfahani A (2004) Acta Chim Slov 51:507Google Scholar