Photocatalytic activity of ascorbic acid-modified TiO2 sol prepared by the peroxo sol–gel method
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Abstract
A TiO2 neutral sol has been successfully prepared by a peroxo sol–gel method using TiCl4 as the precursor and H2O2 as the peptizing agent. However, the particle size of TiO2 is varied, with a wide range of size distribution. Moreover, the sol becomes unstable after a long period of time. Therefore, the purpose of this study was to apply the peroxo sol–gel method to prepare an ascorbic acid-modified TiO2 to ensure enhancement of sol stability, good dispersion of TiO2 nanoparticles with a narrow size distribution, and improvement of photocatalytic activity under UV light and visible light irradiation. The presence of the ascorbic acid sol caused the formation of a charge-transfer complex, resulting in a red shift for TiO2 in the visible light spectrum region through the specific Ti–O–C linkage of ascorbic acid and TiO2 which can extend the limitation to applications of TiO2. It was demonstrated that AA-modified TiO2 particles with different concentrations of ascorbic acid addition were dispersed in a relatively stable, well-dispersed colloidal suspension with a narrow size distribution, as confirmed by DLS result. The optimum observed ascorbic acid/TiO2 molar ratio of 0.75 represents the highest photocatalytic activities under both UV light and visible light irradiation. Thus, it can be seen that the addition of ascorbic acid as a surface modifier improves the photocatalytic activity, prevents particle agglomeration, and provides a very stable TiO2 colloidal system with individual dispersion of titania particles.
Graphical Abstract
Keywords
Ascorbic acid Charge-transfer complex Methylene blue Surface modifier Titanium dioxideReferences
- 1.Teoh WY, Scott JA, Amal R (2012) Progress in heterogeneous photocatalysis: from classical radical chemistry to engineering nanomaterials and solar reactors. J Phys Chem Lett 3:629–639CrossRefGoogle Scholar
- 2.Chong MN, Jin B, Chow CWK, Saint C (2010) Recent developments in photocatalytic water treatment technology: a review. Water Res 44:2997–3027CrossRefGoogle Scholar
- 3.Hashimoto K, Irie H, Fujishima A (2005) Photocatalysis: a historical overview and future prospects. Jpn J Appl Phys 44:8269–8285CrossRefGoogle Scholar
- 4.Fujishima A, Rao TN, Tryk DA (2000) Titanium dioxide photocatalysis. J Photochem Photobiol C Photochem Rev 1:1–21CrossRefGoogle Scholar
- 5.He H, Liu C, Dubois KD, Jin T, Louis ME, Li G (2012) Enhanced charge separation in nanostructured TiO2 materials for photocatalytic and photovoltaic applications. Ind Eng Chem Res 51:11841–11849CrossRefGoogle Scholar
- 6.Zhao B, Chen YW (2011) Ag/TiO2 sol prepared by a sol–gel method and its photocatalytic activity. J Phys Chem Solids 72:1312–1318CrossRefGoogle Scholar
- 7.Chen YW, Chang JY, Moongraksathum B (2015) Preparation of vanadium–doped titanium dioxide neutral sol and its photocatalytic applications under UV light irradiation. J Taiwan Inst Chem Eng 52:140–146CrossRefGoogle Scholar
- 8.Li X, Liu P, Mao P, Xing M, Zhang J (2015) Preparation of homogeneous nitrogen–doped mesoporous TiO2 spheres with enhanced visible-light photocatalysis. Appl Catal B Environ 164:352–359CrossRefGoogle Scholar
- 9.Łabuz P, Sadowski R, Stochel G, Macyk W (2013) Visible light photoactive titanium dioxide aqueous colloids and coatings. Chem Eng J 230:188–194CrossRefGoogle Scholar
- 10.Turkez H (2011) The role of ascorbic acid on titanium dioxide-induced genetic damage assessed by the comet assay and cytogenetic tests. Exp Toxicol Pathol 63:453–457CrossRefGoogle Scholar
- 11.Rajh T, Nedeljkovic J, Chen X, Poluektov O, Thurnaur M (1999) Improving optical and charge separation properties of nanocrystalline TiO2 by surface modification with vitamin C. J Phys Chem 103:3515–3519CrossRefGoogle Scholar
- 12.Ou Y, Lin JD, Zou HM, Liao DW (2005) Effects of surface modification of TiO2 with ascorbic acid on photocatalytic decolorization of an azo dye reactions and mechanisms. J Mol Catal A: Chem 241:59–64CrossRefGoogle Scholar
- 13.Xagas A, Bernard M, Hugot-Le Goff A, Spyrellis N, Loizos Z, Falaras P (2000) Surface modification and photosensitisation of TiO2 nanocrystalline films with ascorbic acid. J Photochem Photobiol A Chem 132:115–120CrossRefGoogle Scholar
- 14.Mert EH, Yalçın Y, Kılıç M, San N, Çınar Z (2008) Surface modification of TiO2 with ascorbic acid for heterogeneous photocatalysis: theory and experiment. J Adv Oxid Technol 11:199–207Google Scholar
- 15.Sasirekha N, Rajesh B, Chen YW (2009) Synthesis of TiO2 sol in a neutral solution using TiCl4 as a precursor and H2O2 as an oxidizing agent. Thin Solid Films 518:43–48CrossRefGoogle Scholar
- 16.Moongraksathum B, Chen YW (2016) Preparation and characterization of SiO2–TiO2 neutral sol by peroxo sol–gel method and its application on photocatalytic degradation. J Sol-Gel Sci Technol 77:288–297CrossRefGoogle Scholar
- 17.Monshi A, Foroughi MR, Monshi MR (2012) Modified Scherrer equation to estimate more accurately nano-crystallite size using XRD. World J Nano Sci Eng 2:154–160CrossRefGoogle Scholar
- 18.Alexander L, Klug HP (1950) Determination of crystallite size with the X-ray spectrometer. J Appl Phys 21:137–142CrossRefGoogle Scholar
- 19.Amalraj A, Pius A (2014) Photocatalytic degradation of alizarin red s and bismarck brown r using TiO2 photocatalyst. J Chem Appl Biochem 1:1–7Google Scholar
- 20.Umer A, Naveed S, Ramzan N, Rafique MS, Imran M (2014) A green method for the synthesis of copper nanoparticles using l-ascorbic acid. Revista Matéria 19:197–203CrossRefGoogle Scholar
- 21.Lui G, Liao JY, Duan A, Zhang Z, Fowler M, Yu A (2013) Graphene-wrapped hierarchical TiO2 nanoflower composite with enhanced photocatalytic performance. J Mater Chem A 1:12255–12262CrossRefGoogle Scholar
- 22.Natarajan TS, Bajaj SC, Tayade RJ (2014) Preferential adsorption behavior of methylene blue dye onto surface hydroxyl group enriched TiO2 nanotube and its photocatalytic regeneration. J Colloid Interface Sci 433:104–114CrossRefGoogle Scholar
- 23.Ozawa H, Fukushima K, Sugiura T, Urayama A, Arakawa H (2014) Ruthenium sensitizers having an ortho-dicarboxyl group as an anchoring unit for dye-sensitized solar cells: synthesis, photo- and electrochemical properties, and adsorption behavior to the TiO2 surface. Dalt Trans 43:13208–13218CrossRefGoogle Scholar
- 24.Yang C, Gong C, Peng T, Deng K, Zan L (2010) High photocatalytic degradation activity of the polyvinyl chloride (PVC)–vitamin C (VC)–TiO2 nano-composite film. J Hazard Mater 178:152–156CrossRefGoogle Scholar
