Does size matter? Most people will say yes, and affirm that bigger is better. On the other hand, sometimes smaller can be better, as we recently discussed using superconductors to reduce the size and increase the power of wind generators. Piezo- and pyroelectrical materials, such as PbZr0.2Ti0.8O3 [PZT], have properties that are well-known and demonstrated in larger sizes.
Piezoelectric materials generate a charge when physically stressed, and pyroelectric materials generate a charge when heated. Generally, bigger PZT materials generate more electricity, but this doesn’t work well when trying to integrate PZT macromaterials into ever-smaller electronic devices.
Will making PZT nanomaterials lead to better or worse performance? In order to find out, researchers in University of Illinois at Urbana-Champaign’s Materials Science and Engineering [MatSE] department have been experimenting on PZT nanowires in thin-film depositions. One of the problems with PZT nanowires, though, is they are difficult to work with, as MatSE assistant professor Lane Martin explains:
“Measuring the pyroelectric response of thin films is difficult and has restricted the understanding of the physics of pyroelectricity, prompting some to label it as ‘one of the least-known properties of solid materials.’ This work provides the most complete and detailed modeling and experimental study of this widely unknown region of materials and has direct implications for next generation devices.”
Martin’s team observed that, even on the nanoscale, PZT nanomaterials were effective generating electricity. Depending on the manufacturing process, such PZT thin films could be integrated directly into current electronic devices and still be effective dissipating heat or reducing the size of sensors.