Abstract
A rapid and simple aqueous method has been developed for synthesizing CdTe/CdS core shell quantum dots (QDs) by refluxing glutathione (GSH) with Cd2+ and Te2− precursors at 100 °C without using inert medium. Here GSH has dual role, i.e., as an in-situ source of sulphide for deposition of CdS on CdTe and as a capping agent to stabilize the CdTe/CdS QDs. As the refluxing time was enhanced from 15 min to 105 min, the sizes of the spherical shaped CdTe/CdS QDs increased from 2.8 ± 0.8 nm to 3.9 ± 1.1 nm, the crystalline nature improved, GSH capping content decreased and the CdS shell deposition was increased. The size dependent change in photoluminescence (PL) from green to red was observed. The photoluminescence quantum yield (PLQY) was improved with refluxing time and maximum PLQY was obtained for the batch synthesized by 60 min refluxing. The PL of these QDs were drastically quenched by ppb levels of Cu2+ ions. Instead of the batch with maximum PLQY, the best Cu2+ sensitivity and selectivity was obtained for the batch synthesized by refluxing for 30 min. This is due to optimal GSH capping content required for availability of Cu2+ ions at the surface of the QDs for favorable electron transfer process, confirmed by PL decay kinetic studies.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Journal of Photochemistry and Photobiology A: Chemistry
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
