Integrated Piezoelectric/Pyroelectric Sensing from Organic-Inorganic Perovskite Nanocomposites.

Flexible ferroelectric materials are in high demand in emerging energy harvesting and self-powered sensing electronics. However, current flexible ferroelectric polymers, such as poly(vinylidene fluoride) (PVDF) and P(VDF--trifluoroethylene) [P(VDF-TrFE)], cannot fulfill the requirement of emerging applications because of their low piezoelectric/pyroelectric performance. In this work, using organic-inorganic hybrid perovskite [(4-aminotetrahydropyran)PbBrCl] ferroelectric nanorods as reinforcement and P(VDF-TrFE) as the matrix, we prepared flexible core-sheath piezoelectric nanofibers and pyroelectric nanocomposite films. The core-sheath nanofibers possess a record-high piezoelectric coefficient of 78.1 pC·N, and the output voltage reaches to 192 V, with the maximum power density of 1.04 W·m. On the other hand, the nanocomposite film exhibits a high pyroelectric coefficient of 58.2 μC·m·K at 333 K, which yields a voltage of 6.1 V under 6.6 K temperature fluctuation. An integrated flexible sensing device was prepared by combining piezoelectric nanofibers and pyroelectric films, which can wirelessly detect vibration and temperature fluctuation simultaneously. The integrated device is suitable for pipelines, power equipment, and other scenarios, where vibration and temperature need to be monitored at the same time.