Preparation of titanium dioxide NPs and study of optical parameters as a polymer photocatalytic film

Abstract

In this study, titanium dioxide (TiO2) nanoparticles are combined with a mixture of polymers (polyvinylalcohol PVA, polyethylene-glycol PEG and polyvinylpyrrolidone PVP). Titanium dioxide (TiO2) NPs was formulation by sol-gel process, nanocomposites were prepared with concentration (1, 5, 10, 15, 20 and 25 wt%). TiO2 NPs after subjecting them to a calcination process at a temperature of about 400 â¦C and 700 â¦C and polymer blend of different concentrations (PVA various wt%, PEG constant wt% and PVP constant wt%). A UV-Vis spectrometer was used to determine the optical constants of the prepared-samples. Absorption coefficient, extinction coefficient, refractive-index and optical energy-gap were calculated, it was noticing of absorption coefficient values in calcination 400 â¦C for 25 wt% TiO2 NPs higher than that of other samples. The refractive index of TiO2 at 700 â¦C is higher than that of 400 â¦C due to the different crystalline structure of rutile. The optical energy band gap was determined and it was discovered to decrease from 5.16 eV for (1 wt% TiO2) blended with (PVA 84 wt%, PEG 10 wt% and PVP 5 wt%) up to 3.51 eV (25 wt% TiO2) with concentrations of (PVA 60 wt%, PEG 10 wt% and PVP 5 wt%) as matrix. At a higher calcination temperature of 700 â¦C, TiO2 transitions from the anatase phase to the rutile phase, this change in crystal structure has a significant effect on the value optical dielectric constant real part (εr) which is (16.06). The findings have important ramifications for possible uses these nanocomposites to enable reuse of the photocatalysts, thus extending their useful life.