TiO2 thin films and Ag/TiO2 nanoparticles were prepared by CVD and plasma bombardment method. XRD results showed the presence of Ag nanoparticles in TiO2 matrix. SEM image confirmed formation of Ag nanoparticles. XPS analysis was utilized to study the chemical state of the Ag/TiO2 nanostructure. Statistical surface analysis revealed that since there is a linear relation between logarithmic diagram of Cq(r) and r<Rc~4 mm for all q, both surfaces have self-affine structure. Formation of Ag/TiO2 nanoparticles led to the reduction of roughness of the samples from 0.72 nm to 0.61 nm. Ag/TiO2 nanoparticles represented greater hydrophilicity under UV illumination and visible light compared with TiO2. TiO2 thin films and Ag/TiO2 nanoparticles showed an inhibition for proliferation of the bacteria on their surfaces. Antibacterial activity of the samples contributed to the growth inhibition of the bacteria on their surfaces.

Effect of aging on the properties of titanium dioxide nanoparticles produced by laser ablation process in water is investigated experimentally. The fundamental wavelength of a Q-switched Nd: YAG laser was employed to irradiate a high-purity Ti plate in distilled water at temperatures of 20, 35, 50 and 65oC. Produced nanoparticles were diagnosed by UV–Vis–NIR spectroscopy, X-ray diffraction method, and dynamic light scattering device immediately after production and 1 week after. Bandgap energy of samples was extracted using Tauc method. Size of nanoparticles was increased after a week and their bandgap energy was decreased. Results show that the phase of TiO2 nanoparticles was transited from brookite to rutile after 1 week.

In particular, the inappropriate/inevitably discharge of dye-containing effluents is undesirable because of their color, resistant to the biological treatment systems, toxic, and their carcinogenic or mutagenic nature to life forms. About fifty percent of the washing dye liquor is discharged into the water environment. Fe3O4@SiO2@TiO2 nanoparticles, were prepared, characterized and tested as photocatalyst in the removal of Reactive Black B (RBB) dye by a photocatalytic process. The effect of photocatalyst concentration, pH and temperature in the photo degradation kinetics is discussed in terms of the Langmuir–Hinshelwood (L-H) model. SEM and TEM characterizations confirmed the Fe3O4@SiO2@TiO2 nanoparticel, revealed that the obtained particles a spherical morphology with sizes about 100 nm. The DRS pattern of Fe3O4@SiO2@TiO2 shows the energy band gap value of photocatalyst is 2.75 eV. The presence of Fe3O4, SiO2 and anatase TiO2 in the as-synthesis magnetic nanoparticle were confirmed by FTIR and XRD analysis. The Fe3O4@SiO2@TiO2 photocatalyst in combination with ultraviolet irradiation and under optimal conditions can destroy 100% of RBB after 120 min. Furthermore, the magnetic photocatalyst was efficiently separated from the solution with the help of a magnet and shown the capable of reusability up to 10 times without reducing their efficiency.

In this work, the TiO2 nanoparticle modified carbon ionic liquid electrode (CILE) was employed as a sensitive sensor to investigate the electrochemical behavior of indomethacin (IND). This nanocomposite sensor has been fabricated by incorporation of TiO2 nanoparticles and the ionic liquid 1-hexylpyridinium hexafluorophosphate (HPFP). The surface of the electrode was studied by scanning electron microscopy (SEM). Differential pulse voltammetry (DPV) was used for quantification of sub-micromolar amounts of IND. Electrochemical parameters of the electrode reaction of IND, including the electron transfer coefficient (α ) and the electron-transfer number (n), were calculated by cyclic voltammetry (CV) methods. Under selected conditions, the anodic peak current was linear for the concentration of IND in the broad range of 1. 0 × 10-7-1. 0 × 10-4 M with the detection limit of 2. 1 × 10-8 M. Moreover, the analytical performance of the proposed method for the determination of IND content in plasma samples was evaluated with good sensitivity and acceptable recoveries.