Multisource energy harvesting using (Ba,Ca)(Zr,Ti)O ₃ oscillating under temperature gradient

Abstract The concept of multisource energy harvesting has attracted attention in order to harvest multiple types of energy in a single material. In this work, Pb‐free (Ba,Ca)(Zr,Ti)O 3 (BCZT) ceramics were used to investigate a combination of piezoelectric and pyroelectric energy harvesting behavior. The temperature dependence of the permittivity and the pyroelectric coefficient was measured, and the pyroelectric properties of BCZT were expected to improve near its orthorhombic–tetragonal phase transition temperature T O–T (∼40°C). The output voltage and current were measured using a BCZT plate, where the BCZT was oscillated under a temperature gradient to apply mechanical stress and temperature fluctuation simultaneously. The measured output voltage from the combined piezo‐ and pyroelectric contributions at a frequency of 2 Hz and with a load resistance of 10 MΩ was 1.4 times higher than the sole piezoelectric output voltage. The resulting combined output voltage was confirmed by finite element simulation.