High Performance Near-Room-Temperature Pyroelectric Energy Harvesting Characteristics of Ferroelectric-Semiconductor Composites

Environment-friendly lead-free pyroelectrics are indispensable for pyroelectric generators to extract energy from low-gradient waste heat to power portable electronic devices. The pyroelectric response near room temperature is essential for high performance energy harvesters, which is unfortunately limited to lead-free ferroelectrics. Herein, BaTiO3-based ferroelectric-ZnO semiconductor composites were reported to exhibit superior pyroelectric energy harvesting characteristics near room temperature. The role of ZnO on the improved ferroelectric characteristics is elucidated through impedance and Rayleigh analysis. Notably, more than 100% enhancement in pyroelectric coefficient (7250 μC/(m2 K)) is displayed by the composite at 45 °C, making it a suitable candidate for pyroelectric energy harvesting applications. The composite showed the figure of merit of pyroelectric energy harvesting FE = 3.032 kJ/(m3 K2), which is the highest value near room temperature among the reported results.