Silver ion release from electrodes of nanotubes of TiO2 impregnated with Ag nanoparticles applied in photoelectrocatalytic disinfection

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Chemistry., 2014-03, Vol.278, p.1-8
• Main Authors: Brugnera, Michelle Fernanda, Miyata, Marcelo, Fujimura Leite, Clarice Queico, Zanoni, Maria Valnice Boldrin
• Format: Article
• Language: English
• Subjects: Ag impregnation; Ag release from Ti/TiO2–Ag; Disinfection; Mycobacterium; Nanotubes TiO2
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/j.jphotochem.2013.12.020

•TiO2 nanotubes electrode impregnated with Ag nanoparticles was made.•The Ag+ lixiviation was monitored by anodic stripping voltammetry.•Antimicrobial behavior of Ti/TiO2–Ag was evaluated using UV and visible irradiation. Self-organized TiO2 nanotubes arrays electrodes were impregnated with 0–16% of Ag nanoparticles (Ti/TiO2–Ag) using different procedures. The electrodes were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and photocurrent vs potential curves. The best results were obtained by electrode prepared by photochemical reduction, after immersion in a solution AgNO3 0.05M (pH 8). The monitoring of Ag+ lixiviation by anodic stripping voltammetry at glassy carbon electrode indicated that a maximum of 2.5×10−6M is released in the first 40min of treatment, but it is neglected when used subsequently. Moreover, the antimicrobial behavior of electrodes Ti/TiO2–Ag applied in photoelectrocatalysis presented 100% disinfection in 3min by using UV irradiation and 99.6% in 30min with visible irradiation. In addition, the analysis of silver in solution along the reaction shows a negligible lixiviation and a high stability of the surface silver deposits.