Effect of sol–gel pH on XRD peak broadening, lattice strain, ferroelectric domain orientation, and optical bandgap of nanocrystalline Pb1.1(Zr0.52Ti0.48)O3

• We used a simple method to fabricate the PZT sub-micron powders at low temperature.
• The peak broadening (XRD) and lattice strain (SSP) are in agreement for all pHs.
• For smaller particles, tetragonality decreases as broadening peaks is increasing.
• The highest tetragonality and c oriented ferroelectric domains are observed at pH 4.
• The A(3TO) transverse optical vibration confirm the existence of perovskite phase.

Nanocrystalline Pb1.1(Zr0.52Ti0.48)O3 (PZT) samples were prepared using a citrate–nitrate sol–gel process near the morphotropic phase boundary. The effect of pH on the lattice parameters (tetragonality and lattice constants), crystal structure [strain broadening, relative phase content, ferroelectric domain (FD) orientation and nanocrystallite size], microstructure (grain size and particle morphology) and optical bandgap was investigated. The samples were characterized using X-ray diffraction (XRD), the size strain plot (SSP) method, Fourier-transform infrared spectroscopy, and the classical Tauc relation. The particle morphology was investigated using field-emission scanning electron microscopy. The XRD results revealed a perovskite structure and coexisting tetragonal and rhombohedral phases for all PZT samples. Lattice strain and peak broadening were determined from SSP and XRD results. The behavior of these parameters was in agreement for all pH values. The optical bandgap for PZT was estimated from UV-vis absorption spectra. We found that for PZT the maximum relative tetragonal phase content, c/a ratio, and FD orientation along the a-axis occurred at pH 4.