Effect of pH on Structure, Optical, and Dielectric Properties of BaTiO3 Nanoparticles

Abstract

AbstractBarium titanate (BTA) nanoparticles are prepared by low‐temperature hydrothermal technique with varying pH from 9 to 12. The X‐ray diffraction (XRD) patterns confirm that the BTA nanoparticles with pH ranging from 9 to 11 show the existence of few small secondary phases (*) related to tetragonal structure along with the prominent cubic phases. But for sample with pH = 12, the XRD patterns confirm the presence of cubic phases without secondary phases. The morphology evidences the existence of almost spherical‐shaped grains (field‐emission scanning electron microscopy), and nanoparticles (high‐resolution transmission electron microscopy) in case of all samples. The energy dispersive spectra confirm the presence of Ba, Ti, and O elements among all samples. Besides, the photocatalytic activity is noticed for all samples. Using the Tauc's plots, optical band gap is determined. The dielectric constant (at pH = 12) is ≈15.10 while the dielectric loss is ≈1.231 suggesting the sample is suitable for charge stored capacitor applications. The dielectric modulus and impedance spectra are recorded in order to evaluate the polarization and conduction mechanism.