Enhanced photocatalytic and antibacterial activities of Ag-doped TiO₂ nanoparticles under visible light

In this paper, we report the photocatalytic and antibacterial activities of nanosized Ti_1-xAg_xO₂ (0.00 < x < 0.08) photocatalyst synthesized by sol-gel method. The X-ray diffraction (XRD) and Raman spectra reveal single phase anatase structure for all substituted samples, ruling out the presence of any secondary phase. This is well supported by TEM micrographs which show that shapes of the nanoparticles are non-spherical. UV- visible spectrum illustrates that an absorption edge shifts toward the visible region. The 4.0 mol % of Ag-doped TiO₂ shows 96% degradation of methylene blue (MB) within 60 min under visible light irradiation and exhibit highest photocatalytic performance. The active catalyst has superb stability and durability, maintaining its high degradation efficiency as more as 89% after the five successive runs. An enhancement in bactericidal activity is also observed against bacterial strain (Escherichia Coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Enterobacter Cloacae) with increased Ag substitution.