Photocatalyst Based on Nanostructured TiO2 with Improved Photocatalytic and Antibacterial Properties

Materials (Basel). 2023 Dec 5;16(24):7509. doi: 10.3390/ma16247509.

Abstract

This study shows an easy way to use electrochemistry and plasma layering to make Cobalt-Blue-TiO2 nanotubes that are better at catalysing reactions. Once a titanium plate has been anodized, certain steps are taken to make oxygen vacancies appear inside the TiO2 nanostructures. To find out how the Co deposition method changed the final catalyst's properties, it was put through electrochemical tests (to find the charge transfer resistance and flat band potential) and optical tests (to find the band gap and Urbach energy). The catalysts were also described in terms of their shape, ability to stick to surfaces, and ability to inhibit bacteria. When Cobalt was electrochemically deposited to Blue-TiO2 nanotubes, a film with star-shaped structures was made that was hydrophilic and antibacterial. The band gap energy went down from 3.04 eV to 2.88 eV and the Urbach energy went up from 1.171 eV to 3.836 eV using this electrochemical deposition method. Also, photodegradation tests with artificial doxycycline (DOX) water were carried out to see how useful the study results would be in real life. These extra experiments were meant to show how the research results could be used in real life and what benefits they might have. For the bacterial tests, both gram-positive and gram-negative bacteria were used, and BT/Co-E showed the best response. Additionally, photodegradation and photoelectrodegradation experiments using artificial doxycycline (DOX) water were conducted to determine the practical relevance of the research findings. The synergistic combination of light and applied potential leads to 70% DOX degradation after 60 min of BT/Co-E irradiation.

Keywords: antibiotics; antimicrobial; blue-TiO2 nanotubes; nanostructures; photocatalytic.

Grants and funding

This work was supported by the following grant agreements: a grant of the European Social Fund from the Sectoral Operational Program Human Capital 2014–2020, through the Financial Agreement with the title “Training of Ph.D. students and postdoctoral researchers in order to acquire applied research skills—SMART”, Contract no. 13530/16.06.2022—SMIS code: 153734.; and a grant of the Ministry of Research, Innovation and Digitization, CNCS—UEFISCDI, project number PN-III-P1-1.1-TE-2021-0417, within PNCDI III.