Salvia officinalis-derived rutile TiO₂NPs: production, characterization, antibacterial evaluation and its effect on decolorization

This study reports a novel precursor for the ecofriendly and low cost biosynthesis of economically important titanium dioxide nanoparticles (TiO2NPs) using Salvia officinalis. TiO(OH)2 was used for the biosynthesis of nanoparticles with the aqueous solution of Salvia officinalis leaf extract. The evaluation of the biosynthesis of TiO2NPs were achieved by UV–vis, XRD, SEM and AFM studies. The results obtained spectrophotometrically were reassuring as pointing an expeditious biosynthesis of TiO2NPs with surface plasmon resonance at 405 nm. The formation and nano-crystalline nature of the TiO2NPs were evaluated by the XRD spectrum by the reflections at 2θ values 27.97°, 31.81°, 40.33°, 49.85°, 53.85°, 63.59° and 73.07°. The main peak of 2θ = 27.97° that correspond to 110 crystallographic surface of the structure was implied that biosynthesized TiO2NPs are rutile. The SEM images showed polydisperse nanoparticles with spherical shapes and ranging between 50–120 nm. The surface morphology was revealed by AFM analysis showing the presence of both individual and agglomerated TiO2NPs. Antibacterial activity was investigated against S. aureus and E. coli, and results evaluated that the TiO2NPs exhibited significant activities towards both bacteria with zone of inhibition in diameters 11.7 ± 1.9 and 10.5 ± 1.5 mm, respectively. Also, TiO2NPs analyzed against azo dyes Reactive Black 5, Reactive Blue 19 and Brilliant Blue R and the photocatalytic activity performances were found as 69, 74 and 79%, respectively.