Pyroelectric energy harvesting devices based-on Pb[(MnxNb1−x)1/2(MnxSb1−x)1/2]y(ZrzTi1−z)1−yO3 ceramics

Abstract

The energy conversion and harvesting properties of pyroelectric devices depend on many aspects, including the properties of pyroelectric materials, the structure of the devices, and so on. In this work, the capability of harvesting energy using Pb[(MnxNb1−x)1/2(MnxSb1−x)1/2]y(ZrzTi1−z)1−yO3 (PMnN–PMS–PZT) ceramics was studied. For this purpose, three different Zr/Ti compositions, i.e. 94/6, 95/5 and 96/4 (in molar ratio) of the ceramics were prepared and characterized. The ceramic with 95/5 of Zr/Ti was found to have optimized pyroelectric properties and consequently used to fabricate pyroelectric energy harvesting devices. Three different device configurations, including a monolithic ceramic, ceramic arrays and multilayered ceramics were studied, and the innovated multilayered ceramic structure proposed in this study showed advantages in energy conversion and collection efficiency, which were evaluated by using an oven and a Peltier cell as heating and cooling methods. The maximum densities of surface charge achieved for the three types of ceramic structures are 7.19×10−6C/cm2, 6.59×10−6C/cm2, 1.55×10−5C/cm2, respectively, which are in general higher than that of the commercial lead zirconate titanate (PZT-5H). We also investigated the effects of temperature change frequency on the electrical response by using the monolithic ceramic device as an example. At an operating frequency of 70mHz, the pyroelectric device shows an induced energy as high as 2.873μJ and a power density of 4.857mW/cm3. The obtained results indicate that our proposed PMnN–PMS–PZT devices in general has a better pyroelectric performance than the commercial lead zirconate titanate (PZT-5H) pyroelectric devices, and may have potential applications in ultra-low-power devices and in wireless network systems.