Demonstration of a Flexible Pressure Sensor with Novel Piezoelectric Materials

Piezoelectrics are materials that have the ability to generate electrical charges when an outside stress is applied. Furthermore, the research into alternative piezoelctrics can be essential in the production of many commonly used products like hand lighter and pace makers. The piezoelectric properties of a material can be measured by running a high voltage current through the material to align its dipoles and testing the electric response the material can produce when pressure is applied. Some organic and inorganic materials are naturally piezoelectric, and are also inexpensive to produce. This would allow for manufacturers to move away from PZT (Lead Zirconium Titanate), which possesses strong piezoelectric effects, but the lead found within it is extremely hazardous to society and the environment. Here we show that PVDF (Poly(vinyldene)difluoride), a weaker piezoelectric but less hazardous material, plus an organic/inorganic material can be an inexpensive, lead-free, and easy-to-fabricate alternative to PZT. The results confirmed that a combination of PVDF and (Histammonium) ZnCl₄ was able to create a functioning active device and produced the best results due stronger piezoelectric effect compared to (Histammonium) CuCl₄and (Histammonium) CoCl₄. Each material generates an electric signal proportional to the applied pressure. Our results demonstrate how each material can be used to increase the piezoelectric effects of a PVDF polymer. We anticipate that our research will be used as a starting point for other methods of strengthening weaker piezoelectrics as better alternatives.