Journal of Applied Sciences and Nanotechnology

Titanium dioxide nanoparticles were produced in this work by laser ablation of a high purity titanium objective immersed in distilled water. Optical and structural properties of the obtained TiO₂ NPs using a Q-switched Nd: YAG laser of 1064nm wavelength with different laser energy (80, 100, 120, 140, and 160) mJ at 100 pulses was studied. The produced TiO₂ NPs were characterized employing UV-VIS Spectrophotometer, X-ray diffraction, and scanning electron microscopy (SEM). The obtained TiO₂NPs showed a decrease in transmittance in the region of the UV spectrum and an increase in the visible spectrum region. The estimated optical band gap of the TiO₂NPs was 3.89eV, 3.8eV, and 3.70eV at 80, 120 and 160mJ laser energy, respectively. The as-produced TiO₂NPs appear to be a Brookite crystalline phase with the preferential orientation along (200) direction. The scanning electron microscopy assays showed that the TiO₂ NPs have a cauliflower shape. Results show that with increasing the energy of laser pulse, the size of nanoparticles was increased noticeably. Where the particle size and its morphology are affected by laser energy.

The polycrystalline thin films were deposited on glass substrate at room temperature by pulsed laser deposition PLD technique. The effects of annealing treatment by used the Oil Thermal Annealing (OTA) process on the structural, optical and electrical properties of ZnO thin film films were investigated. The film structure was investigated by X-ray diffraction to indicate that the heat treatment after the OTA process gives the optimized condition of crystalline. The transmission spectrum of the film was measured by UV-V is spectrophotometer, and the Urbach energy and forbidden band width were calculated. The surface topography of the film was observed by scanning electron microscopy (SEM) image of the ZnO thin film at the OTA process shows the changes in the shape and size of the grains. The atomic force microscopy (AFM) effect of heat treatment was demonstrated by the change in the surface roughness of the ZnO thin film. The electrical properties of thin film were optioned by Hall Effect technique. That these improvements in the ZnO thin film physical properties were annealing temperatures by OTA at 150 °C, 200 °C, 250 °C and 300 °C.