TiO2 nanoparticles versus TiO2–SiO2 nanocomposites: A comparative study of photo catalysis on acid red 88

A novel, simple, less time-consuming and cost-effective wet chemical technique was used to synthesis
TiO2 nanoparticles and TiO2–SiO2 nanocomposites using Titanium tetra isopropoxide (TTIP) as a precursor
relatively at low temperature in acidic pH. Titania sol was prepared by hydrolysis of TTIP and was
mixed with silicic acid and tetrahydrofuran mixture. The reaction was carried out under vigorous stirring
for 6 h and dried at room temperature. The resulting powders were characterized by UV–Visible spectroscopy,
Fourier transform infrared (FT-IR), X-ray diffraction, scanning electron microscope (SEM) and transmission
electron microscope (TEM). The grain size of the particles was calculated by X-ray diffraction,
surface morphology and chemical composition was determined from scanning electron microscopy–
energy dispersive spectroscopy, metal oxide stretching was confirmed from FT-IR spectroscopy, band
gap was calculated using UV–Visible spectroscopy. Surface area of the composite as calculated by BET
analyzer and it was found to be 65 and 75 m2/g for TiO2 and TiO2–SiO2 respectively. The photocatalytic
experiments were performed with aqueous solution of acid red 88 with TiO2 and TiO2–SiO2 batch studies
for 4 h irradiation, direct photolysis of TiO2 and TiO2–SiO2 contributed 94.2% and 96.5% decomposition in
solar radiation for the optimized concentration of acid red 88.