Síntesis química y caracterización morfológica y óptica de nanopartículas de sulfuro de cadmio

Abstract

This document presents the study carried out on nanoparticles (NPs) of cadmium sulfde (CdS). The general objective was to synthesize CdS NPs and to determine experimental conditions that allow to control their shape and size, and to develop the comparison of optical methods of size estimation. The optical methods used were validated by classical techniques such as DLS (Dynamic Light Scattering) and electronic micrography (SEM and TEM). Four different synthesis systems were used, all based on the formation of reverse micelles (water in oil) in microemulsions. The modifcation of properties like the limit of absorbance and fluorescence of the nanoparticles is important, because these will make them suitable for possible future applications. The chemical synthesis systems used were: 1) microemulsion formed with water, AOT and heptane; 2) microemulsion originating from water, AOT and hexane; 3) microemulsion constituted by synperonic, isoctane, water and thiol, and 4) microemulsion formed with mesquite gum and water. Each of these systems allowed obtaining nanoparticles with different sizes from the variation of parameters such as the amount of water and surfactant or the dose of precursor added to the microemulsion, during the synthesis process.