Synthesis and Sensing Behavior of Pure and Doped BaTiO₃

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.