A visible light mediated synergistic catalyst for effective inactivation of E. coli and degradation of azo dye Direct Red-22 with mechanism investigation

Abstract

Novel zirconium and silver co-doped TiO2 nanoparticles were fabricated and utilized as effective multifunctional visible light photocatalysts for inactivation of bacteria (E. coli) as well as degradation of azo dye (Direct Red-22) for the first time.

Visible-Light-Active Doped Metal Oxide Nanoparticles: Review of their Synthesis, Properties, and Applications

“…133 Zr-doped anatase TiO 2 nanoparticles were synthesized by Naraginti et al by using ZrO(NO 3 ) 2 and TTIP as zirconium and titanium precursors, respectively. 137 The same group also codoped the zirconium with silver using AgNO 3 and calcined at 450 °C to obtain nanoparticle powders, 7 to 19 nm in diameter. Analysis by EDX showed near stoichiometric ratios for AgTiO 2 (1:1:2) and ZrAgTiO 2 (1:1:1:2).…”

“…In contrast, a narrowing of the bandgap upon zirconium substitution in anatase TiO 2 NPs was observed by Naraginti et al down to 2.98 eV. 137 These two studies suggest that zirconium by itself is a weak dopant for tuning the absorption edge and narrow the anatase TiO 2 bandgap. However, codoping with Zr and Ag showed an even narrower bandgap of 2.82 eV and a greater suppression of electron−hole recombination than the monodoped samples.…”

“…In a more recent study using the same precursors, Benjwal et al observed that solvothermal methods afforded anatase-phase Zn and Mn codoped nanospheres, while hydrothermal methods generated anatase–rutile−brookite triphasic nanorods . Zr-doped anatase TiO 2 nanoparticles were synthesized by Naraginti et al by using ZrO­(NO 3 ) 2 and TTIP as zirconium and titanium precursors, respectively . The same group also codoped the zirconium with silver using AgNO 3 and calcined at 450 °C to obtain nanoparticle powders, 7 to 19 nm in diameter.…”

Engineering the Morphology and Crystal Phase of 3 D Hierarchical TiO2 with Excellent Photochemical and Photoelectrochemical Solar Water Splitting

“…This was confirmed by monitoring the concentrationo fN BTC + at 259 nm by UV/Vis absorption spectroscopy. [66] The concentration of NBTC + was found to decreasea taf aster rate for R-1 than for AR-2 ( Figure S11a). This is due to transfero fe lectrons from the CB of the rutile phase to the anatase phase of TiO 2 in AR-2.…”

Efficient detoxification of triclosan by a S–Ag/TiO2@g-C3N4hybrid photocatalyst: process optimization and bio-toxicity assessment

“…3b) revealed that the Ag 3d 5/2 and Ag 3d 3/2 binding energies were observed at 368.3 and 374.2 eV respectively indicates the presence of Ag 0 . 34,35 The S 2p spectra (Fig. 3c) showed two peaks at 169.8 eV and 170.2 eV, which could be ascribed to S 2p 3/2 and S 2p 1/2 , respectively.…”