Comparison of the antimicrobial photocatalytic activities of SiO2 and AuSiO2 nanostructures in water decontamination

© 2023 Wiley Periodicals LLC..

Photocatalytic disinfection of Escherichia coli suspension by silicon dioxide nanoparticles and silicon dioxide/gold nanocomposite in a batch reactor is investigated experimentally and results are compared. Silica nanoparticles were synthesized by Stöber method and pulsed laser ablation method was employed to prepare gold nanoparticles in distilled water. Composition of two nanoparticles species was carried out, using the second harmonic pulse of Nd:YAG laser, whose wavelength is in the absorption spectra of gold nanoparticles. Results confirm a decrease in the bandgap energy of silica nanoparticles after composition. Escherichia coli were selected as an indicator of the microbial water contamination. Disk diffusion method was used to evaluate the antimicrobial potential of SiO2 and AuSiO2 nanostructures. Photocatalytic activities of both nanostructures were examined in dark, and under the irradiation of UV and visible light. In all conditions, the performance of Au@SiO2 nanocomposites was higher than SiO2 nanoparticles. In dark condition the higher biocidal nature and activity of Au nanoparticles and for the case of UV radiation, decreasing the bandgap energy and recombination rate of SiO2 nanoparticles after composition with Au increased the efficiency. For the case of visible light radiation, surface plasmon resonances effects, and local heat of Au nanoparticles were responsible for increasing the efficiency. RESEARCH HIGHLIGHTS: Doping large bandgap semiconductors nanostructures, such as silica with metal nanoparticles, such as gold will improve their photocatalytic activity to work in visible light. In this mechanism, gold nanoparticles act as effective traps to prevent the recombination of photogenerated electron-hole pairs. Other mechanisms, such as Schottky barrier formation, surface plasmon resonance absorption of gold nanoparticles, and biocidal nature of the gold nanoparticles are effective in increasing the efficiency of Au doped silica nanostructures.

Medienart:

E-Artikel

Erscheinungsjahr:

2024

Erschienen:

2024

Enthalten in:

Zur Gesamtaufnahme - volume:87

Enthalten in:

Microscopy research and technique - 87(2024), 5 vom: 22. Apr., Seite 896-907

Sprache:

Englisch

Beteiligte Personen:

Alizadeh, Mahsa [VerfasserIn]
Dorranian, Davoud [VerfasserIn]
Sari, Amir Hossein [VerfasserIn]

Links:

Volltext

Themen:

Au@SiO2 nanocomposite
Disc diffusion method
Escherichia coli
Journal Article
Laser ablation
Photocatalysis

Anmerkungen:

Date Revised 01.04.2024

published: Print-Electronic

Citation Status PubMed-not-MEDLINE

doi:

10.1002/jemt.24486

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM366404075