Preparation and formation mechanism of porous TiO2 films using PEG and alcohol solvent as double-templates

• Published in: Journal of sol-gel science and technology Vol. 30; no. 3; pp. 239 - 248
• Main Authors: Bu, Shaojing, Jin, Zhengguo, Liu, Xiaoxin, Du, Haiyan, Cheng, Zhijie
• Format: Journal Article
• Language: English
• Published: Heidelberg Springer 01.06.2004; Springer Nature B.V
• Subjects: Alcohol; Anatase; Chemistry; Colloidal gels. Colloidal sols; Colloidal state and disperse state; Dip coatings; Exact sciences and technology; General and physical chemistry; Glass substrates; Immersion coating; Infrared analysis; Infrared spectroscopy; Organic chemistry; Polyethylene glycol; Pore formation; Pore size; Porosity; Porous materials; Sol-gel processes; Solvents; Stabilizers (agents); Thin films; Titanium dioxide; polyethylene glycol; Film; Transition element compounds; Alcohol; double-templates; Porous material; Thin film; Ethylene oxide polymer; porous thin films; Preparation; Titanium oxide; mechanism; Formation mechanism; TiO2
• ISSN: 0928-0707; 1573-4846
• DOI: 10.1023/B:JSST.0000039531.31632.e6

Porous nanocrystalline TiO2 anatase thin films have been synthesized on glass substrates via a sol-gel dip-coating method. The coating sol was obtained by suppressed hydrolysis of Ti(OC4H9)4 through the addition of complexing molecules as stabilizers in an alcohol solution containing polyethylene glycol (PEG). Chemical changes taking place during the sol-gel process were discussed based on IR spectra analysis. A model concerning the pore formation was established to explain the role of PEG and solvent with core-shell configuration as double-templates. The structural characteristics of porous TiO2 films were found to greatly depend on the concentration and molecular weight of PEG, the types of stabilizing agents and solvents. The pore size of the films was tunable in the range of 10–500 nm and their surface area varied from 51 to 72 m2·g−1.