Atomic Force Microscopy Study of TiO2 Films Obtained by the Sol-Gel Method

Academia Romana, Bucureşti, Hunedoara, Romania
Journal of Sol-Gel Science and Technology (Impact Factor: 1.53). 12/1997; 13(1):769-773. DOI: 10.1023/A:1008673812626


Atomic Force Microscopy (AFM) was used to study the influence of thermal treatments on the structural and textural properties of the sol-gel TiO2 films obtained from Ti(OC3H7i)4. X-ray diffraction (XRD), ellipsometric and porosity measurements have also been made.
The TiO2 sol-gel films were homogeneous, transparent and amorphous. Heat treatments in the 400–600°C range indicate that the films have a strong tendency to crystallization. The high initial homogeneity of the TiO2 films was preserved during the crystallization process. AFM shows that the thermally treated films exhibit uniform, monodispersed crystals.

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    • "Atomic force microscopy (AFM) is a very important tool for examining the thin film surface morphology at the nanoscale. During the last decade, a considerable interest has been expressed regarding the application of AFM for structural studies of different materials [20] [21] [22]. "
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    • "Titanium oxide TiO 2 has universally been recognized as one of the better photocatalysts in heterogeneous photocatalysis applications as it combines two important complementary features for a photocatalyst: good UV absorption efficiency for the light harvesting process and good adsorption capacities, due particularly to the density of OH – groups of amphoteric character. However, the band gap energy requires that near-UV light be used to photo activate this very attractive photocatalyst [1] [2] [3]. "
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