Photoluminescent Properties of TGA-Capped CdTe Quantum Dots
An environmentally friendly synthesis was developed to fabricate aqueous CdTe quantum dots (QDs) using thilglycolic acid (TGA) as a capping agent. Optimal preparation conditions including pH (11.2) and TGA/Cd molar ratio (1.5:1) resulted in CdTe QDs with high photoluminescence (PL) quantum yield up to 56%. The TGA-capped CdTe QDs exhibited tunable PL from green to red. Lifetime measurement indicated that the average lifetime of the TGA-capped QDs increased with increasing their sizes (27.5 and 37.2 ns for the QDs with PL peak wavelength of 607 and 636 nm, respectively). The PL of the QDs revealed the dependence of temperature, in which the QDs exhibited a red-shifted PL peak with increasing temperature. Such PL behavior depended strongly on the QD sizes.
Shiquan Liu and Min Zuo
Z. M. Yuan et al., "Photoluminescent Properties of TGA-Capped CdTe Quantum Dots", Advanced Materials Research, Vols. 306-307, pp. 1262-1265, 2011