Rietveld analysis of La3+/Al3+ modified PbTiO3 ceramics

The polycrystalline samples of (Pb0.70La0.30)(AlxTi1−x)O3 (PLAT) (x = 0.0, 0.05, 0.10, 0.15, 0.20) were synthesized by conventional solid-state reaction technique and annealed at two different temperatures. A single phase X-ray diffraction pattern was recorded with cubic symmetry of the space group Pm−3m.The Bragg–Brentano geometry is used for indexing, structural solution and Rietveld analysis for our powder samples. The detailed structural study was analyzed by employing Rietveld refinement techniques with the help of the Fullprof Program. The lattice parameters, cell volume, Wyckoff position of the atoms, bond lengths and angles have been calculated from the Rietveld analysis with the help of Powder Cell Program and by taking the refined parameter a stable crystal structure was suggested. It was observed that lattice parameter and cell volume decreases with increase of Al concentration. The crystallite size has been compared by three different methods: Scherrer's formula, Hall–Williamson method and Rietveld method. The scanning electron microscope (SEM) analysis of the samples shows the uniform microstructure with no abnormal grain growth and the grain size increases with annealing temperature and decreases with the increase of Al concentration. The elemental analysis was confirmed by energy dispersive spectrum analysis.