A Method of Fabricating Dielectric with Enhanced Dielectrostriction Effect by Applying Electric field

• Main Authors: Yu, Huiyang, Ye, Xin, Pan, Yifei, Guo, Chenxi, Chen, Zefang, Tu, Jiacheng, Wu, Zhe, Ren, Qingying, Huang, Jianqiu, Li, Yifeng
• Format: Conference Proceeding
• Language: English
• Subjects: Capacitors; dielectrostriction effect; flexible dielectric; Nanocomposites; Nanoparticles; Powders; Pressure sensors; Sensitivity; Three-dimensional printing; wide range pressure detection
• ISSN: 2168-9229
• DOI: 10.1109/SENSORS52175.2022.9967185

In this paper, a method to enhance the dielectrostriction effect is proposed. This method can be used to fabricate the highly pressure-sensitive dielectric layer. These dielectrics are mainly made of Polydimethylsiloxane (PDMS) and nanoparticles, the nanoparticles are doped into PDMS and the electric field is applied to control the distribution of nanoparticles which then exhibit a chain-like distribution. The nanoparticles encapsulated by PDMS can be regarded as electric dipoles. They tend to be attracted and arranged along the direction of the electric field when applied an electric field. As a result, a strong coupling effect will generate between the electric dipoles, which will be further enhanced when a pressure load is applied. This effect is called dielectrostriction effect, which is not very obvious in the randomly doped dielectric but could be obviously enhanced by the method of applying an electric field when curing. The dielectric fabricated in this way displays a superior pressure-sensitive performance. For instance, the capacitor based on iron nanoparticles exhibits a stable pressure response over a wide pressure scope (0kPa-250kPa) and a high sensitivity (1.8%/kPa) when the mass ratio of nano-iron powder to PDMS is 35%. This method of fabricating dielectric is expected to be used in flexible pressure sensor with wide detection range and high sensitivity.