High-frequency thermal-electrical cycles for pyroelectric energy conversion

We report thermal to electrical energy conversion from a 150nm thick BaTiO₃ film using pyroelectric cycles at 1kHz. A microfabricated platform enables temperature and electric field control with temporal resolution near 1μs. The rapid electric field changes as high as 11×10⁵kV/cm-s, and temperature change rates as high as 6×10⁵K/s allow exploration of pyroelectric cycles in a previously unexplored operating regime. We investigated the effect of phase difference between electric field and temperature cycles, and electric field and temperature change rates on the electrical energy generated from thermal-electrical cycles based on the pyroelectric Ericsson cycle. Complete thermodynamic cycles are possible up to the highest cycle rates tested here, and the energy density varies significantly with phase shifts between temperature and electric field waveforms. This work could facilitate the design and operation of pyroelectric cycles at high cycle rates, and aid in the design of new pyroelectric systems.