Multifunction applications of TiO ₂ /poly(vinyl alcohol) nanocomposites for laser attenuation applications

The effects of TiO ₂ nanoparticles on the PVA matrix can design new nanocomposites with new features in the structural, thermal and optical properties. Different nanocomposites films of TiO ₂ -doped PVA are prepared using solution casting method. TiO ₂ /PVA nanocomposites have been examined by using X-ray diffraction (XRD), (DTA), and UV–Vis–NIR spectrophotometric data. The XRD reveals the existence of both anatase and rutile phases of TiO ₂ . The crystalline size, Inter-crystallite separation, and the inter-planar distance are estimated and PVA crystallinity is enhanced as reflected from XRD studies. DTA studies conclude that the total crystallinity of the nanocomposites is improved after the addition of TiO ₂ . Optical characterizations of TiO ₂ /PVA nanocomposite films have been determined. The transmittance spectrum of 37.037 wt % TiO ₂ -doped PVA showed a blocking of the light in the wavelength region from 190 to 1275 nm which supports this material to be used as UV–Vis–NIR CUT-OFF laser filters with wide scale. The estimated direct optical band gap is varied from 5.6 eV to 2.11 eV with increased TiO ₂ content. For analysis, the dispersion of the refractive index (n) and the dispersion parameters (E _o and E _d ), Wemple–Didomenico single oscillator model is used. Optical limiting was measured and analyzed for the TiO ₂ /PVA nanocomposites and the laser He–Ne laser power was attenuated by increasing the TiO ₂ -contents. It is possible to utilize TiO ₂ /PVA nanocomposites in different aspects of laser power attenuations, wide-scale optical filters and UV-blocking for saving the human skin.