Synthesis and characterization of silver-titania nanocomposites prepared by electrochemical method with enhanced photocatalytic characteristics, antifungal and antimicrobial activity

Abstract

The paper deals with the synthesis of silver-titania (Ag-TiO2) nanocomposites with enhanced photocatalytic, antifungal and antimicrobial characteristics. Ag nanoparticles have been electrochemically deposited on the commercially available nano-TiO2 powders involving the so-called “sacrificial anode” technique. The obtained nanocomposites were characterized by X-ray diffraction, XPS and Raman spectroscopy to get information on their composition and structure. Particle size distribution and stability of Ag-TiO2 based colloidal solutions have been determined from dynamic light scattering and zeta potential measurements. The recorded UV–vis diffuse reflectance spectra evidenced the presence of an absorption band located in the range of 475–525 nm and the presence of a tail as well, suggesting a better photocatalytic activity. The photoreactivity of the synthesized Ag-TiO2 nanocomposite as well as the influence of Ag content were evaluated for the degradation of Orange II dye under UV irradiation (λ = 365 nm). The heterogeneous photocatalytic degradation rate follows pseudo first order kinetics. Antifungal and antimicrobial efficacy evaluation showed that the synthesized Ag-TiO2 nanocomposites are significantly more active than pure titania. Keywords: Silver-titania nanocomposites, Electrochemical synthesis, Microstructure characterization, Photocatalyst, Antifungal