Preparation Of Titania Films Research Articles

Design of titania porous films controlled by precursors’ viscosity for photocatalytic application

Porous transparent films of TiO2 (anatase) were obtained by controlled hydrolysis of titanium tetraisopropoxide (sol-gel method) in the presence of a polyethylene glycol as a template agent with molar masses of 300, 600 and 1000 g/mol and α-terpineol as a high viscosity agent. The efficiency of the films in the photocatalytic degradation of Rhodamine 6G is correlated with their porosity and films’ thickness. Higher photoactivity of the obtained films compared with a non-porous TiO2 film was observed for TiO2(300) and TiO2(600) whereas the lower activity was noted for TiO2(1000). The size of anatase crystals is increased proportionally to the precursor’ gelation time and is accompanied by a decrease of the specific surface area and porosity of the film. The presence of polyethylene glycol slowed down TIPT’s hydrolysis rate. It is shown that the viscosity of the precursor is the key factor in the preparation of titania films with certain crystal size, thickness and high photocatalytic activity.

Preparation of Titania Films with Cohered Nanosized Particles Using Improved Liquid Phase Deposition Process

Preparation of Titania Films with Cohered Nanosized Particles Using Improved Liquid Phase Deposition Process

Preparation of Titania Film by Pyrolysis of Chelated Tetrabutyl Titanate

Preparation of titania films by pyrolysis of chelated tetrabutyl titanate was investigated. Films of tetrabutyl titanate were first formed on glass substrates by spin coating, and TiO2 films were prepared after annealing at 500°C. The influences of annealing temperature, AcAc concentration, Ti(OBu)4 concentration, PEG amount and coating times on the photocatalytic properties of TiO2 films were studied, and the films were characterized by XRD and DTA.

Preparation of Titania Film by Vapor Decomposition of Chelated Tetrabutyl Titanate

The vapor decomposition of chelated tetrabutyl titanate on glass substrate was used for the preparation of titania films. The influences of decomposition temperature, chelant concentration on the photocatalytic properties of titania film were investigated. The films were characterized by XRD, ATR and the precursor solution was characterized by DTA.

Preparation of titania films by laser CVD and their microstructures

Preparation of titania films by laser CVD and their microstructures

Aqueous Titanate Sols from Ti Alkoxide- -Hydroxycarboxylic Acid System and Preparation of Titania Films from the Sols

Aqueous titanate sols were prepared by reactions of titanium tetraisopropoxide (TIP) with α-hydroxycarboxylic acids in water. IR and Raman spectra, and elemental analyses of the precipitates obtained from the sols revealed that the carboxylates were chelated to titanium but the Ti species were polymerized to form a cluster that had a colloidal nature. Spin-coating of titania (TiO2) thin films from these sols was also examined. Interestingly, it was found that (004) preferentially oriented anatase films with refractive index of 2.54 were obtained from TIP-lactic acid-NH3 (1:1:1, molar ratio) aqueous sol. This crystallographic orientation was characteristic of the TIP-lactic acid-NH3 (1:1:1) system, and was not affected by the kinds of substrates used and the heating rate of the film. TEM observation indicated that small anatase grains had already formed at 200°C. Therefore, the crystallographic orientation might depend strongly on the structure of the chemical species of the precursor solutions.