Structural Characterization of Some As-S-Sb-Te Nanostructured Materials

Abstract

Nanostructured As-S-Sb-Te semiconductors were synthesized and characterized by Xray fluorescence analyzer (XRF), X-ray diffraction, and optical absorption methods. The X-ray diffraction patterns of ivestigated powders show the presence of amorphous and nanocrystalline phases with the structural units As2S3, Sb2S3 and Sb2Те3. The transmission spectra in the region of wavenumbers ν=10006000 cm-1 show a high transparence just with a single weak absorption band at ν=2340 cm-1 caused of the presence H2S impurity. For the alloys of (As2S3)x(Sb2S3)1-x.system, with increasing of the Sb2S3 trigonal structural units in the above mentioned system, the absorption edge is shifted toward lower photon energy, that corresponds to the optical band band gap about Eg.=2.34 eV for As2S3, 2.1 eV for (As2S3)0.65(Sb2S3)0.35, 1.92 eV for (As2S3)0.35(Sb2S3)0.65 and 1.73 eV for Sb2S3.