Thiophenol-capped ZnS quantum dots

Abstract

Free-standing, stable, single-sized, and highly pure ZnS nanosize particles or quantum dots are synthesized using a chemical route. The dimension of the quantum dots as estimated from x-ray diffraction was about 7 and 15 A. The optical band gap for these particles was 5.2 and 4.8 eV, respectively, as compared with the bulk energy gap of 3.8 eV. These results are compared wit.h the elfective mass approximation. The observations indicate that only particular-sized stable particles can be synthesized which should have minimum energy coniiguration. X-ray photoelectron spectroscopy was utilized for examining stoichiometry and purity of the sample.

Effect of Capping Agent Concentration on Photophysical Properties of Zinc Sulfide Nanocrystals

“…Band gap computed from absorption edge has been reported as 2.57 eV. Mahamuni et al [8] have obtained absorption peak at 238 nm (5.2eV) and 258 nm (4.8eV) for ZnS nanoparticles of size 7Å and 23Å respectively, but no peak was observed for a particle size of 23 Å. This result is in agreement with our results.…”

“…(3 [8]. The lattice parameter has been computed as 5.34 Å, which is very close to the standard value (5.42 Å).…”

Mechanoluminescence and thermoluminescence of Mn doped ZnS nanocrystals

“…Three different peaks are obtained at 2y values of 29.501, 48.801, and 57.801. This shows that the samples have the zinc blende structure and the peaks correspond to diffraction at (1 1 1), (2 2 0), and (3 1 1) planes, respectively [32]. The lattice parameter has been computed as 5.31Å, which is very close to the standard value (5.42Å).…”

Experimental and Theoretical Study of the Mechanoluminescence of ZnS:Mn Nanoparticles

“…These peaks correspond to diffraction at the (111), (220), and (311) planes, respectively. 20,21 The lattice constant was calculated to be 5.31 Å , which is very close to the standard value (5.42 Å ). The XRD pattern confirms the samples have the zinc blend structure.…”