10.1186/2228-5326-3-56

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

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  • Rostam Moradian*1,
  • Mohammad Elahi2,
  • Ahmad Hadizadeh2,
  • Mahmoud Roshani3,
  • Atefeh Taghizadeh2,
  • Reza Sahraei3,
  1. Department of Physics, Razi University, Kermanshah, IR Nano Science and Nano Technology Research Center, Razi University, Kermanshah, IR Computational Physical Science Research Laboratory, Department of Nano-Science, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran, IR
  2. Department of Physics, Razi University, Kermanshah, IR
  3. Department of Chemistry, Ilam University, Ilam, IR
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Published in Issue 2013-11-14

How to Cite

Moradian, R., Elahi, M., Hadizadeh, A., Roshani, M., Taghizadeh, A., & Sahraei, R. (2013). Structural, optical, and electrical properties of thioglycolic acid-capped CdTe quantum dots thin films. International Nano Letters, 3(1 (December 2013). https://doi.org/10.1186/2228-5326-3-56
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Abstract

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.

Keywords

  • CdTe quantum dots,
  • Thin films,
  • Optical properties,
  • Electrical conductivity
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