Structural, optical, and electrical properties of thioglycolic acid-capped CdTe quantum dots thin films

Abstract

Water-soluble cadmium telluride (CdTe) quantum dots (QDs) were synthesized using thioglycolic acid as capping agent; this reaction was carried out at pH = 10.2 and refluxed at 100°C for 18 h. The CdTe QDs prepared at various reflux times from 1 to 18 h were coated on the glass substrates to obtain thin films of the CdTe QDs with the same thickness. The CdTe thin films were characterized by X-ray diffraction, ultraviolet-vis spectroscopy, and photoluminescence spectroscopy. The absorption thresholds of the CdTe thin films are blueshifted by about 0.65 eV with respect to the bulk value (1.5 eV), due to the quantum size effect as expected from the nanocrystalline nature of the CdTe QDs. X-ray diffraction showed that the films consisted of small CdTe nanocrystallites, 2.91 to 3.57 nm in size, showing quantum size effects. The effects of temperature on the electrical properties of the films were studied in detail. Electrical resistivity measurements were carried out for different films in the temperature range from 343 to 463 K. It is shown that activation energy increases by increasing the reflux time.

Effect of Heating Time on the Structural Properties of Cadmium Telluride Nanoparticles Prepared by Aqueous Solution Method with Organic Stabilizing Agent

“…and from the empirical fitting expression given by Eq. ( 2) [17], and nanoparticle size estimated from the SEM images According to the SEM (VEGA3 TESCAN, mode SE from TESCAN ORSAY HOLDING,a.s.,Czech Repuplic) images shown in Fig. 2 the prepared nanoparticles heated for 30 min got larger in size but still individually distinct with approximately equal size as shown in Fig.…”

Efficient photocatalytic and photovoltaic applications with nanocomposites between CdTe QDs and an NTU-9 MOF

“…HR-TEM and SAED images of the selected area of the CdTe/NTU-9 sample were highlighted with the presence of lattice fringes and diffraction rings that matched the standard CdTe phase, as reported in the literature. [69][70][71][72] The results of HR-TEM analysis (Fig. S2 †) also indicated the porous nature of both the MOF and its composite.…”

Morphology, optical, and electric properties of polymer-quantum dots nanocomposites: effect of polymeric matrix

“…Most of the studies reported in the literature have been focused on the research of new methodologies to modify QDs to be embedded into polymers by simply mixing both materials. Only a few studies have been devoted to understand the size and structural evolution of QDs in the resulting nanocomposites [19,20], and how the chemical interaction between the capping ligands and the polymers can influence the charge transport within the nanocomposites [21].…”