A Facile Platform for Photocatalytic Reduction of Methylene Blue Dye By CdSe-TiO2 Nanoparticles

Abstract

Herein, we report on the demonstration of enhanced photocatalytic reduction of methylene blue (MB) dye using a physical mixture (w/w ratio: 50:1–9) of TiO2 nanoparticles (size ≈ 20 ± 1 nm) and CdSe nanocrystals (size ≈ 3.0 ± 0.2 nm). It was found that at the highest content of the nanocrystals (9 mg) in the physical mixture, 67% reduction in the dye concentration could be achieved in a period of 60 min to prepare a physical mixture. Nano-catalyst characterization was accomplished using XRD, SEM, FTIR, UV-visible and Raman spectroscopy. The results showed that the prepared nanocatalyst could remove MB dye from waste water under the presence, as well as in the absence of UV- irradiation, while pristine TiO2 nanoparticles or the CdSe nanocrystals did not possess sufficient photocatalytic activity in the absence of UV-radiation. It is concluded that presence of CdSe nanocrystals at a mass concentration of less than 5% can be used for the remediation of water polluted with industrial dyes.