Growth, characterization and estimation of lattice strain and size in CdS nanoparticles: X-ray peak profile analysis

Abstract

This work is based on the growth, characterization and estimation of lattice strain and crystallite size in CdS nanoparticles by X-ray peak profile analysis. The CdS nanoparticles were synthesized by a non-aqueous solvothermal method and were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), Raman and UV–visible spectroscopy. XRD confirms that the CdS nanoparticles have the hexagonal structure. The Williamson–Hall (W–H) method was used to study the X-ray peak profile analysis. The strain–size plot (SSP) was used to study the individual contributions of crystallite size and lattice strain from the X-rays peaks. The physical parameters such as strain, stress and energy density values were calculated using various models namely, isotropic strain model, anisotropic strain model and uniform deformation energy density model. The particle size was estimated from the TEM images to be in the range of 20–40 nm. The Raman spectrum shows the characteristic optical 1LO and 2LO vibrational modes of CdS. UV–visible absorption studies show that the band gap of the CdS nanoparticles is 2.48 eV. The results show that the crystallite size estimated from Scherrer’s formula, W–H plots, SSP and the particle size calculated by TEM images are approximately similar.