| Abstract Scope |
Two different 0.9KNbO3-0.1BaNi0.5Nb0.5O3-δ ceramics, KBNNO-I and KBNNO-II, have been synthesized using NiO and Ni acetate, respectively, as Ni precursors. Their microstructure was investigated using XRD and Raman spectroscopy, and TEM was used for the first time. Compared to KBNNO-I, TEM revealed KBNNO-II to have a larger grain size (100-300 nm) and no NiO impurities, which agrees with XRD results. This is also responsible for the lower band gap (2.48 eV), higher saturation polarization (10.54 µC/cm2), and larger dielectric constant of KBNNO-II compared to KBNNO-I. Our findings demonstrate that this impurity-free synthesis method retains favorable ferroelectric characteristics and significantly enhances optical absorption, making the material a more promising candidate for photovoltaic applications. This work contributes to developing lead-free, environmentally friendly ferroelectric materials for next-generation solar cells |