Antiviral and Antibacterial Effects of Silver-Doped TiO₂ Prepared by the Peroxo Sol-Gel Method

Abstract

<jats:p>A series of multifunctional silver-doped titanium dioxide (Ag/TiO<jats:sub>2</jats:sub>) nanocomposites with various silver contents were synthesized by the peroxo sol–gel method using TiCl4 as a precursor and H<jats:sub>2</jats:sub>O<jats:sub>2</jats:sub> as a peptizing agent. The sol was used to coat a glass substrate, thereby forming a thin film. The antiviral and antibacterial activities of the Ag/TiO<jats:sub>2</jats:sub> films and their use in the photocatalytic degradation of an aqueous solution of methylene blue were investigated. The as-prepared materials were characterized using high-resolution transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The antiviral and antibacterial activities of the samples were tested against <jats:italic>Escherichia coli</jats:italic>, the influenza A virus (H1N1), and enterovirus. It was observed that an optimum Ag:TiO<jats:sub>2</jats:sub> weight ratio of 1:100 enabled the highest activity in the photocatalytic degradation of an aqueous solution of methylene blue under irradiation with either ultraviolet or visible light. Moreover, the same composition remarkably exhibited extremely high antibacterial and virucidal effectivenesses greater than 99.99% against <jats:italic>E. coli</jats:italic> and infectious viruses after illumination with ultraviolet A. The presence of silver on TiO<jats:sub>2</jats:sub> significantly enhanced its photocatalytic activity. Thus, the excellent photocatalytic activities and reusability of the Ag/TiO<jats:sub>2</jats:sub> nanocomposite render it applicable as a coating material for several purposes.</jats:p>

Photocatalytic Antibacterial Effectiveness of Cu-Doped TiO2 Thin Film Prepared via the Peroxo Sol-Gel Method

“…Figure 2 depicts TEM images of TiO2 and 0.5Cu/TiO2 particles. The morphology of the TiO2 particles prepared via the peroxo sol-gel method is best described as an elliptical shape with particle size of 40-60 nm and 15-30 nm for long and short axes, respectively [3,7,12,[23][24][25]. In Figure 2b, HRTEM image displayed the lattice fringe of TiO2 of 0.327 nm, corresponding to the anatase (101) plane.…”

“…For use as antibacterial agents, copper and its compounds achieve antibacterial activity by the accumulation of copper ions within cells, eventually causing degradation of cell membranes [19][20][21]. Using titanium tetrachloride (TiCl4) as a precursor and H2O2 as a peptizing agent, previous studies have proposed a peroxo sol-gel method for the synthesis of neutral TiO2 sol [22][23][24][25]. The advantages of this method include not needing a calcination process to obtain the anatase structure of TiO2, as well as the ability to use H2O2 as an oxidizing agent.…”

“…Using titanium tetrachloride (TiCl 4 ) as a precursor and H 2 O 2 as a peptizing agent, previous studies have proposed a peroxo sol-gel method for the synthesis of neutral TiO 2 sol [22][23][24][25]. The advantages of this method include not needing a calcination process to obtain the anatase structure of TiO 2 , as well as the ability to use H 2 O 2 as an oxidizing agent.…”

Nanomaterials for Airborne Virus Inactivation: A Short Review

“…This can be attributed to the fact that Pt enhances the efficiency of virus adsorption and semiconductor charge separation. Moongraksathum et al ( 2019 ) synthesized silver-deposited titanium dioxide (Ag/TiO 2 ) nanocomposite sol and coated it on a glass substrate to form a thin film. It was found that the sample had almost 100% antiviral effect on H1N1 virus and enterovirus 71 under UVC or visible light irradiation.…”

Facile Synthesis of Ag/TiO2 by Photoreduction Method and Its Degradation Activity of Methylene Blue under UV and Visible Light Irradiation

“…[6] [7] [8]. The XPS spectra were collected using Al Kα radiation at a voltage and current of 20 kV and 30 mA, respectively.…”