Mesoporous zinc oxide supported silica-titania nanocomposite: Structural, optical, and photocatalytic activity

Abstract Sol-gel-based titania nanoparticles (TNPs), Silica-titania nanocomposite (STNC), and zinc supported silica-titania nanocomposites (Z/STNC) are synthesized at low temperature. FESEM/EDX shows that ZNPs are homogeneously distributed in the STNC. The STNC has average roughness (Ra) ~6 nm, surface area ~340 m2/g, pore volume ~0.24 cm3/g, and particle size 4 nm ± 0.3 nm, which decrease down to Ra ~5 nm, large surface area 351 m2/g, pore volume 0.4 cm3/g, and particle size 3 nm ± 0.4 nm due to filling of STNC pores by Zn species. STNC is revealed 94% transmission, refractive index 1.34 at 633 nm, and bandgap 2.7 eV, which decreased down to 80% transmission, large refractive index 1.38, and low bandgap 2.25 eV after ZNPs doping. The Z/STNC observed high photocatalytic activity 92%, R2 ~98%, and rate constant 0.011 min−1 in the photodegradation of phenol red under UV-light irradiation.