Barium titanate–bismuth ferrite/polyvinylidene fluoride nanocomposites as flexible piezoelectric sensors with excellent thermal stability

Flexible piezoelectric sensors based on barium titanate–bismuth ferrite/polyvinylidene fluoride BT–BFO/PVDF nanocomposites were prepared via electrospinning for pitch-catch applications. The 20% BT–BFO/PVDF piezoelectric sensor had the 75% β phase and exhibited a dielectric constant of 55.71, a dielectric loss of 0.035 and a signal voltage of 3.35 V at 100 kHz, indicating significant improvement compared to traditional PVDF sensors. Moreover, the sensor can maintain a stable signal voltage of 2.0 V and dielectric constant variation of less than 15%, even when the temperature gradually increased from 20 ℃ to 120 ℃. The flexible piezoelectric sensor that can endure temperature variations shows great potential in mass concrete.