Designs of Pyroelectric Devices for Green Energy Applications

• Main Authors: An-Shen Siao, 蕭安盛
• Other Authors: Chun-Ching Hsiao
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/p3dj6u

碩士 === 國立虎尾科技大學 === 機械設計工程研究所 === 101 === Lead zirconate titanate (PZT) has widely been used in thermal energy harvesting by pyroelectric effect, which can convert thermal energy into electricity for energy recycling in green technology. Temperature variation rates in pyroelectric materials significantly affect electrical outputs of pyroelectric devices. In the present study, the structures of pyroelectric materials were designed for improving the temperature variation rate by finite element method, and then the pyroelectric devices with variuos three-dimensional patterns were fabricated by dicing saw apparatus and sandblast etching for enhancing the electrical outputs of the pyroelectric devices. The pyroelectric devices with various trench widths, depths and patterns under various measured temperatures and periods were further discussed. In the simulation results, the partially covered type with a 50 μm trench width and a 150 μm trench depth improved the temperature variation rate about 402.65 %, compared to the fully covered type. The temperature variation rate in the vortex-like type was higher than that in the fully covered type about 54.08 %. In the experimental results, the vortex-like type with a 200 μm trench width and a 170 μm trench depth fabricated by sandblast etching improved the electrical generation rate about 56.63 %, compared to the fully covered type. Moreover, the vortex-like type was used to store a 1.1 mJ electrical energy in a 22 μF electrolytic capacitor with 143 seconds via a full-bridge circuit. The vortex-like type was 2.6 times the charged speed of the fully covered type. Therefore, the sandblast etching can fabricate complex three-dimensional patterns in the pyroelectric devices for ameliorating the thermal energy harvesting.