Facile synthesis and optimization of ZnSe–GSH quantum dots by hydrothermal method

Abstract

Water-soluble ZnSe quantum dots (QDs) with high luminescence were synthesized by a simple hydrothermal method using selenium powder and zinc acetate solution as precursors, and L-glutathione (GSH) as a stabilizer. In addition, the photoluminescence properties of ZnSe QDs under different conditions (precursor ratios, precursor solution pH, and hydrothermal temperature) were thoroughly investigated. The morphology and structure of as-synthesized ZnSe-GSH QDs under optimized experimental conditions were determined by HRTEM, XRD, and TG-DTA. Results showed that the ZnSe-GSH QDs were tiny nanocrystals with quasi-sphere particles of ∼3 nm size with core-shell structure. The formation and growth mechanism of the core-shell structure were discussed in detail. When the synthesis process was carried out under optimized hydrothermal conditions (reaction temperature, 140 C; reaction time, 45 min; pH value of precursor solution, 10.0; GSH-to-Zn mole ratio, 1.2; and Se-to-Zn mole ratio, 0.2), the as-synthesized ZnSe-GSH QDs emitted blue-purple fluorescence (375 nm) when excited at 321 nm.

Enhancement effect of defect fluorescence of ZnSe quantum dots on a heterojuction of ZnSe quantum dots and gold nanoparticles

“…At present, control and optimization of the fluorescent properties from ZnSe QDs is still a crucial issue in their practical application [11,12]. Such control capability has impacted many new fields such as surface-enhanced Raman scattering [13,14], LEDs [15,16], QD lasers [17,18], photocatalysis [19], and biology [20].…”

Local structure of Ge quantum dots determined by combined numerical analysis of EXAFS and XANES data

“…While EXAFS is a powerful technique of choice for structural characterization of amorphous systems, it provides limited information about the local symmetry of disordered samples due to limited (usually to the first coordination shell) structural information. For characterizing QDs, there are added problems of complex nanoscale morphology (Ke et al, 2015;Sun et al, 2015;Zhang et al, 2014) and possible metastable phases (Chiu et al, 2006;Nelmes et al, 1993;Selli et al, 2013) due to the small particle size and/or surface effects. At the same time, the near-edge portion of the XAS signal, i.e.…”

CdS Nanowires with Large Aspect Ratio and Their Composite with CuS and Au Nanoparticles

“…CdS nanowires as a typical wurtzite structure semiconductor can be used as photonic circuit elements and electrically driven nanoscale lasers. [9][10][11][12][13][14][15] CdS nanorods and nanowires have been prepared in literature. For example, Zou"s group reported on a single wurtzite CdS nanowires with an average diameter of * Author to whom correspondence should be addressed.…”