Synthesis and photocatalytic activity of polymer stabilized cadmium selenide quantum dots-titanium dioxide nanocomposites

Abstract

In this work, we report the synthesis of the nanocomposites of cadmium selenide (CdSe) quantum dots (QDs) and titanium dioxide nanoparticles (TiO2 NPs), and their use in the photocatalytic degradation of an organic dye. Titanium dioxide nanoparticles are a multifaceted large band gap metal oxide semiconductor that has been subjected to innumerable research studies in the past decades. TiO2 NPs exhibit characteristic properties depending upon their morphology, crystal structure, size and the method of synthesis that makes them suitable and efficient for different applications. The synthesized CdSe QDs were then used to sensitize TiO2 NPS in order to form CdSe QDs-TiO2 nanocomposites. The morphology of the QDs were investigated by high resolution-transmission electron microscopy. Fluorescence spectroscopy studies were performed to determine the absorption and emission peaks of the CdSe QDs. The band gap increased of pristine TiO2 NPs and CdSe decorated TiO2 NPs were evalued using UV–visible diffuse reflectance spectroscopy. The XRD pattern of the synthesized nanocomposites depicted the formation of anatase phase of TiO2. These nanocomposites were then used for the photocatalytic degradation of methylene blue (MB) dye.