Synthesis of photocatalysts for the reduction of hexavalent chromium by modification of TiO2 with nanoparticles of Cu and/or CDS

• Published in: Tehnika
• Main Authors: Petrović Jana Lj., Radovanović Željko M., Lazarević Slavica S., Barać Nemanja M., Janaćković Đorđe T., Petrović Rada D.
• Format: Article
• Language: English
• Published: Union of Engineers and Technicians of Serbia 2024-01-01
• Subjects: titanium dioxide; photocatalytic reduction; cr(vi); visible irradiation
• Online Access: https://scindeks-clanci.ceon.rs/data/pdf/0040-2176/2024/0040-21762404385P.pdf
• ISSN: 0040-2176; 2560-3086

In this work, TiO2-based composite photocatalysts were synthesized for the photoreduction of Cr(VI) by deposition of CdS and/or Cu nanoparticles. Oak leaf extract was used as a reducing agent for the synthesis of Cu nanoparticles. Although the deposited amount of Cu was small (~ 1.1 wt%), it resulted in a shift of the absorption edge to the visible region and a significantly higher efficiency compared to TiO2. Deposition of ~ 3 wt% CdS resulted also in a higher activity under the visible light compared to TiO2, but lower compared to Cu-TiO2. The best results were obtained with the ternary photocatalyst, probably due to the formation of a z-scheme in which the deposited Cu acts as a mediator for electron transfer between CdS and TiO2. The addition of citric acid as a hole "scavenger" allowed a further increase in activity, even in the case of TiO2.