Nanoarchitectonics of Niobium-Doped,Lead-Free BLT (Ba0.97La0.02Ti0.98Nb0.016O3) for Electrical Properties with Unusual d.c Bias Voltage Independence

Polycrystalline sample of Ba_0.97La_0.02Ti_0.98Nb_0.016O₃ (distinguished as BLTi_0.98Nb_0.016) has been prepared through Molten-Salt-Flux reaction route. The XRD, surface morphology, absorption spectra, impedance, and dielectric behaviors were employed to typify the prepared polycrystalline ceramic. The XRD analysis reflects that obtained perovskite having the pure-tetragonal structure with space group P4/mmm. As of the absorption spectra, the optical band gap (Eg), Urbach energy (Eu), and refractive index values have designed. The electrical properties of synthesized compound have been inspected via complex impedance spectroscopy vs. frequency (f) (10² Hz–10⁶ Hz) within the d.c-bias voltage range [0.5 V–5 V]. The fitting of the Nyquist plot exposes that both intra- and intra grains contribute to relaxation and the grain limits are more resistive and capacitive than the grains. Modulus analysis confirms that relaxation in our sample is of non-Debye nature and d.c-bias voltages dependent. Depending on the frequency, the change of ε′ can be discussed founded on the principle of interfacial polarization of the Maxwell–Wagner category. BLTi_0.98Nb_0.016 shows notable frequency independent relative studied properties, it is a potential candidate for devices.