Caracterização Estrutural e Óptica da Solução Sólida Nanoestruturada Sn(Se1-xSx) com x = 0, 0,24, 0,5, 0,76 e 1 produzida por Mecano-Síntese

Abstract

SnX2 semiconductors (where X = Se, S, Te) have been extensively studied in recent years due to the variety of applications for electronic, optical and optoelectronic devices, as well as being a material of low toxicity, low cost, own layered structure and having the possibility to regulate the optical energy gap by modifying the proportion of the material stoichiometry. In this context, this study had produced a nanostructured solid solution Sn(Se1−xSx) to x = 0, 0,24, 0,5, 0,76 and 1 using the Mecano-Synthesis technique. The samples were investigated using X ray Diffraction, Rietveld Method, Differential Scanning Calorimetry and Ultraviolet-visible Spectrophotometry techniques which demonstrated that samples were formed with an orthorhombic structure with anisotropic microdeformation of 4,9% on average. It was also possible to verify that the diffractogram peaks shift to the right as we gradually replace selenium with sulfur into the solution. The samples kept stable at temperatures up to 200ºC and they disintegrated at temperatures above 600ºC. Direct and indirect energy optical gaps were also observed from samples that showed different values from the literature and may be linked to two main factors: 1) the method used to obtain the energy absorption in which water was used as a solvent to solubilize with the sample and 2) mass concentration of samples in solvent. The values gained from the optical energy gap range from 0,67 to 4,0 eV for indirect gap and 4,1 to 5,4 eV for direct gap.