Synthesis and Sensing Behavior of Pure and Doped BaTiO\(_3\)

Abstract

Barium titanate (BaTiO₃) is a widely studied perovskite material with exceptional ferroelectric, piezoelectric, and dielectric properties, making it highly suitable for sensing applications. Its perovskite structure enables spontaneous polarization, tunable bandgap, and high dielectric permittivity. Doping BaTiO₃ with transition metals (Fe, Co, Ni) and rare-earth elements (La, Sc, Gd) significantly enhances its electrical properties, oxygen vacancy concentration, and stability, improving its gas, humidity, and temperature sensing capabilities. Various synthesis techniques, including solid-state reaction, sol-gel, hydrothermal, and co-precipitation methods, influence BaTiO₃’s structural and functional properties. Doping alters charge transport, defect chemistry, and adsorption characteristics, optimizing its sensing performance. Gas sensing in BaTiO₃ is governed by surface interactions, electron transfer mechanisms, and defect-induced conductivity changes. Its ability to detect CO₂, NH₃, and H₂ is enhanced by specific dopants that modulate electronic states and oxygen vacancy formation. Piezoelectric and ferroelectric properties enable BaTiO₃’s use in pressure sensors, energy harvesters, and actuators, where mechanical stress induces charge generation. Doping improves domain wall mobility and response time, increasing its sensitivity and reliability. Comparative analysis shows doped BaTiO₃ outperforms pure BaTiO₃ in selectivity, response time, and sensing efficiency.