Optimizing the Au Particle Doping Size for Enhanced Photocatalytic Disinfection under Low-Intensity Visible Light.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40704641.
- Also identified by DOI 10.1021/acsnano.5c07650 and PMC identifier 12333410.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
Here, we present the effect of 1.2-9.9 nm Au particles on crystal violet-treated polymer under a low intensity of visible light. The use of Au particles ≤ 6.3 nm promoted charge carrier transfer from crystal violet to Au particles. Photospectroscopy analyses and DFT computations revealed that a change in the electronic band structure caused by the size reduction of the particle altered the charge carrier transfer pathway in crystal violet. Especially for crystal violet─1.2 nm Au particles, charge carrier transfer predominantly occurs at the S<sub>1</sub> of crystal violet because the T<sub>1</sub> state lacks sufficient potential energy for transfer. 1.2 nm Au particles on crystal violet not only most significantly enhanced the generation of O<sub>2</sub>•<sup>-</sup>, H<sub>2</sub>O<sub>2</sub>, and <sup>•</sup>OH by minimizing unnecessary side reactions or energy loss but also showed the most potent disinfection activity against <i>Staphylococcus aureus</i>, even at low visible light flux levels (0.037-0.054 mW cm<sup>-2</sup>), which resulted in a 5.3 log reduction in viable bacteria after 6 h exposure to visible light. This finding provides fundamental insights into the Au effect as a cocatalyst in photocatalysts and the development of light-activated self-sterilizing surfaces that can be applied to various hospital surfaces to prevent the spread of pathogens, which remains a global challenge.