Optical and structural properties of X-doped (X = Mn, Mg, and Zn) PZT nanoparticles by Kramers–Kronig and size strain plot methods

Pure and X doped (X = Mg, Mn, and Zn) lead zirconate titanate nanoparticles (PZT-NPs) were synthesized using sol-combustion method. The xerogel was calcined at temperature of 700 °C for 2 h. The structure of the prepared powders is characterized using X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The XRD results show that the PZT-NPs are formed in perovskite structure with rhombohedral phase. In addition, a small shift was detected in XRD patterns of doped PZT-NPs. Also, the XRD results were analyzed using size strain plot (SSP) to calculate the lattice strain of the prepared samples, which revealed that the lattice strain depends on the different ionic radii of the dopants. To have a better understanding of the optical properties of the pure and doped PZT-NPs, the obtained FTIR spectra were analyzed using Kramers–Kronig method. The results show that there are certain relations between the optical parameters and the wavelength of the incident beam as well as the optical modes. Also, the value of the pure and doped PZT-NPs optical band gaps were estimated using ultra violet and visible (UV–vis) spectroscopy. It was found that the optical properties of the doped samples depend strongly on dopants.