Development of a lead-free colossal dielectric material barium bismuth ferrous oxide for electronic devices

Abstract

Ceramic materials are promising for the ever-increasing demand in next-generation electronic devices. In this regard, we report the development and characterizations (structural, microstructural surface, dielectric, transport, impedance, resistive and current-voltage properties) of a novel complex material Ba3Bi2Fe2O9. Preliminary investigation of the X-ray diffraction (XRD) pattern shows the dual phase nature (cubic and tetragonal phase). The analysis of the Williamson-Hall plot illustrates the average crystallite size and micro-lattice strain are 91.37 nm and 0.002, respectively. The scanning electron microscopic spectrum examines the microstructural surface interface analysis, fractal study and topographic roughness (using the standard ISO25178). The analysis of Maxwell-Wagner dielectric dispersion, relaxation, and transport mechanisms are investigated utilizing dielectric, impedance, and conductivity spectrum accumulated within the experimental frequency (1 kHz–1 MHz) and temperature (298 K–373 K) range. The energy band of intrinsic and ionization regions with different frequencies (1 kHz and 10 kHz) indicates the semiconducting behavior of the material. The presence of non-Ohmic and space charge limited conduction (SCLC) mechanisms is investigated by the varistor constant β1 and β2. The thermistor constant (β) is determined to be 1683.13, and the temperature coefficient of resistance (TCR) is −0.00903, which may be suitable for wearable NTC thermistors and other related device applications.