Caracterização estrutural de nanopartículas dos compósitos [ZnO-NiO] utilizando métodos de análise de perfil da linha na difração de raio X

Abstract

Studies have been carried out involving the production and characterization of [ZnO-NiO] nanoparticles generating multifunctional materials with application in various fields, such as biomedicine, solar cells and optoelectronic devices. Based on this scenario, the objective of this work was to investigate the structural evolution of nanoparticles of the [ZnO-NiO] composites, involving the X-ray diffraction through line profile analysis (APL) to aim determining the structural parameters of crystalline domain sizes and microdeformations. Pure systems of ZnO and NiO were prepared by the protein sol-gel method using nitrate and chloride as sources of NiO, respectively. The [ZnO-NiO] composites were produced in four systems using the two sources of NiO at concentrations of 1% and 10%, where all systems were prepared at a fixed temperature of 550°C in times of 2, 3, 4, 5 and 6 hours. The APL obtained the structural parameters of the systems through the application of Scherrer, modified Scherrer and Williamson-Hall methods, where it also demonstrated the importance of instrumental correction of diffraction measurements. The evolution of the sizes of crystalline domains as a function of these heat treatment times showed similar patterns, with the precursor source of NiO being the most relevant parameter in the dimensions of the sizes of crystalline domains. The results indicated the presence of homogeneous deformation as a function of the displacement of the peaks in these composites. The [ZnO-NiO-nitrate] systems presented results of crystalline domain sizes and microstrain coherent between the methods, unlike the [ZnO-NiO-chloride], in which the divergence was motivated by the validity limit of the methods.