Ag/AgBr/TiO₂ Visible Light Photocatalyst for Destruction of Azodyes and Bacteria.

Abstract

was prepared by the deposition-precipitation method and was found to be a novel visible light driven photocatalyst. The catalyst showed high efficiency for the degradation of nonbiodegradable azodyes and the killing of Escherichia coli under visible light irradiation (λ > 420 nm). The catalyst activity was maintained effectively after successive cyclic experiments under UV or visible light irradiation without the destruction of AgBr. On the basis of the characterization of X-ray diffraction, X-ray photoelectron spectroscopy, and Auger electron spectroscopy, the surface Ag species mainly exist as Ag 0 in the structure of all samples before and after reaction, and Ag 0 species scavenged h VB + and then trapped e CB -in the process of photocatalytic reaction, inhibiting the decomposition of AgBr. The studies of ESR and H 2 O 2 formation revealed that•-were formed in visible light irradiated aqueous Ag/AgBr/TiO 2 suspension, while there was no reactive oxygen species in the visible light irradiated Ag 0 /TiO 2 system. The results indicate that AgBr is the main photoactive species for the destruction of azodyes and bacteria under visible light. In addition, the bactericidal efficiency and killing mechanism of Ag/AgBr/TiO 2 under visible light irradiation are illustrated and discussed.

Visible-Light-Induced Photocatalytic Degradation of Azodyes in Aqueous AgI/TiO2 Dispersion

“…Because of these properties, silver halides have not been studied much in photocatalytic reactions. Recently, we have reported that the novel visiblelight-driven photocatalyst AgBr/TiO2 shows high efficiency in the degradation of nonbiodegradable azodyes and the killing of Escherichia coli under visible light irradiation (12). Our results indicate that AgBr is the main photoactive species for the destruction of pollutants under visible light.…”

Novel Synthesis of Plasmonic Ag/AgCl@TiO2 Continues Fibers with Enhanced Broadband Photocatalytic Performance

“…Afterward, Huang et al [20] found that the modification of TiO 2 with Ag/AgCl obviously improved its photocatalytic activity. However, previous research has mainly focused on the fabrication of nano-sized Ag/AgCl/TiO 2 catalysts, such as nanoparticles [21,22], nanospheres [23], nanoarrays [20,24] and nanofibers [25]. These nano-sized catalysts are difficult to separate directly Figure 1a,c,e, the surface of TF is homogeneous and smooth, while the surface of CTF and S-CTF are rough.…”

Influence of titanium dioxide modification on the antibacterial properties

“…It has been known that during the fi rst minutes bacteria use self-defence and auto-repair mechanisms to protect against the active species generated under irradiation. Oxidation of outer membrane begins gradually but not suffi ciently to cause serious damage to the Unauthenticated Download Date | 5/10/18 6:35 PM bacterial cells 22 . It was assumed that better antibacterial properties presented photocatalyst characterized by similar anatase and rutile crystallite sizes.…”