Energy harvesting is a process of capturing small amounts of energy that would otherwise be lost as light, sound, vibration, movement, or heat. Ferroelectrics, which are inherently piezoelectric and pyroelectric, can be used for energy harvesting through creating an electric field by generating an electric field in the opposite direction, change in pressure, and change in temperature. An example of one of the many ways these materials can be used is in tires, through compression and decompression that occurs when the tire comes in contact with the road as well as through outside temperature change. The energy created can be used in electric cars in order to extend the amount of time it can run before recharging.
The use of ferroelectric nanoparticles could allow for energy harvesting devices to be created less expensively due to the presence of both piezoelectric and pyroelectric properties as well as the increased piezoelectricity and pyroelectricity in nanoscale ferroelectrics. Ferroelectric nanoparticles can also be easily deposited onto a substrate which is less expensive than chemical vapor deposition or other high temperature evaporative manufacturing. The control over many different nanoparticle shapes and sizes may also yield new applications for ferroelectric materials. Additionally, the use of ferroelectric nanoparticles rather than a bulk ferroelectric material may achieve ultrahigh piezoelectric responses once the nanoparticles reach the size at which they exist in a single-domain state.
The ferroelectric nanoparticle aggregates to be used in this work are formed through a simple room-temperature cation exchange in which a solution of a metal chloride salt is injected into a solution of CdSSe graded alloy quantum dots and shaken causing ferroelectric aggregate formation. We expect to enhance these particles through gaining a full understanding of the effects of the metal chloride salt used as well as its concentration on the cation exchange process.