Piezoelectric Material Red

Event Center A & B

Croconic acid was found to be ferroelectric in 2010. At CSUSB we began looking at various salts of this acid for newer materials with ferroelectric properties. Computational chemist at CSUSB (Dr. Kimberly Cousins) found that a particular salt of Croconic acid (Red) had potential to be piezoelectric along all of its crystallographic axis. After being synthesized, the powder x-ray diffraction confirmed that the crystal grew in the correct structural phase as predicted from theory. To test the piezoelectric behavior of the material we created a simple, two parallel plate capacitor with Red as the dielectric material, and thermally evaporated gold electrodes. Applying AC voltage at 1 Hz to the sample and looking for displacements, we were able to detect piezoelectric responses on each axis of the material. The resulting graph, strain Vs Electric field (butterfly curve), is used to find piezoelectric constants. We recorded the piezoelectric constant to be 2E-6 cm/KV and 3E-6 cm/KV for the c and b Axis respectively. The problem is that the best butterfly curve obtained on the a-axis is not symmetrical, so we can consider two different piezoelectric constants from this curve; 1E-4 cm/KV and 8E-6 cm/KV. To compare these values a standard PZT disk was used under similar experimental conditions, which yielded a piezoelectric constant of 2E-4 cm/KV. So the biggest piezoelectric constant obtained from the a-axis curve is in the same order of magnitude as one of the conventional piezoelectric materials. This material is worth pursuing further since the preliminary testing reveals that this could be a promising piezoelectric organic material.