Rietveld analysis of X-ray diffraction pattern of sol-gel synthesized copper oxide nanoparticles

Abstract

We adopted a cost-effective sol-gel method to synthesize copper oxide (CuO) nanoparticles. Formation of well crystalline CuO nanostructures without any impurity was confirmed from the X-ray diffraction (XRD) pattern of the prepared materials. It is also evident that no CuO phase is present in the material. The growth of the nanocrystal was found to be anisotropic as revealed from the intensities of the diffraction peaks. The crystallite size was calculated using the Scherrer formula. It was further observed that the variation of precursor concentration leads to change in the crystallite size. We performed a detail chemistry of this precursor concentration dependence of the growth. Various structural parameters like crystallite size, strain, dislocation density, lattice parameters and specific surface area were calculated from the analysis of the X-ray diffraction pattern. Rietveld simulation for detail analysis of the structure of the synthesized CuO nanoparticles revealed the monoclinic unit cell with lattice parameters : a=4.705511Å, b=3.439857Å, c=5.148335Å, α=γ=90° and β=99.403°. The other Rietveld fitting parameters were also evaluated. The values of Rp, Rwp and Rexp were found to be 4.127%, 5.329% and 4.723% respectively with a χ value of 1.128 which justifies the goodness of fitting.