A 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3-based pyroelectric generator and temperature sensor

We report the extremely-high pyroelectric power generation of a relaxor ferroelectric 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-0.3PT) single crystal. The pyroelectric current and voltage of PMN-0.3PT depend on the electric poling voltage, the temperature-variation rate, and the measurement temperature. Near the structural transition temperatures of the rhombohedral-tetragonal transition (~380 K) and the tetragonal-cubic transition (~410 K), the temperature-induced change in the electric polarization results in a sharp enhancement of the pyroelectric power. Near the tetragonal-cubic transition temperature, i.e., the Curie temperature, we observe a pyroelectric current of ~100 nA and voltage of ~11 V. Near room temperature, we observe a pyroelectric current of ~1.4 nA and voltage of ~0.2 V from the touch of a human finger. These results imply that the relaxor ferroelectric PMN-0.3PT should be quite useful for pyroelectric energy-harvesting and temperature-sensing applications.