Microwave-assisted sol–gel synthesis of TiO ₂ -mixed metal oxide nanocatalyst for degradation of organic pollutant

Titanium dioxide (TiO 2 ) is the most effective photocatalysts for low-cost degradation of organic pollutant; however, the wide band gap and the high recombination rate of the charge carriers are drawbacks that hinders it practical application. In this study, TiO 2 and titanium mixed metal oxides ternary (V/Ag/TiO 2 ) nanocatalyst was synthesized through a microwave-assisted sol–gel route using Ti(C 4 H 9 O) 4 , NH 4 VO 3 , and AgNO 3 as precursors. The XRD analysis of the synthesized TiO 2 and V/Ag/TiO 2 depicts lattice fringes for rutile and anatase crystalline phases. Raman spectra indicate the formation of a mesoporous multiphase sample mixture of rutile and anatase phases. The spectrum shift to the visible light region was demonstrated by the UV-visible spectroscopy analysis. Diffuse reflectance spectroscopy (DRS) reveals a reduced band gap of 2.9 eV for TiO 2 and 2.65 eV for V/Ag/TiO 2 . Brunauer–Emmett–Teller (BET) indicates a large surface area of 92.8 and 84.8 m 2 g −1 for TiO 2 and V/Ag/TiO 2 , respectively. Nitrogen adsorption–desorption isotherm exhibits type IV isotherm, signifying the presence of the mesoporous structure. SEM portrays a cluster of rod-like aggregate particles, while the HRTEM analysis illustrates nanoparticles of rod-like cylindrical shape with a homogeneous size diameter. The synthesized nanocatalyst demonstrated a significant photocatalytic ability in the degradation of methyl orange (MO) and methylene blue (MB). V/Ag/TiO 2 shows higher activity in the visible region. Thus, the present report suggests efficient, suitable, and economical microwave-assisted sol–gel techniques to yield V/Ag/TiO 2 nanocatalysts with harnessed photocatalytic performance for the degradation of toxic organic pollutants in the presence of visible light irradiation.