Research Terms
Industrial Engineering Manufacturing Engineering
Keywords
Famu-Fsu College Of Engineering
Industries
Industrial Engineering Manufacturing Engineering
The present invention is a novel technology capable of continuously manufacturing on a large scale of superstructure based on a broad range of nanoparticles. The technology has the potential to be a cost-effefctive way to manufacture nanomaterials based macroscopic parts and components, whose properties approach to those of the individual nanoparticles.
Flexible, stretchable, highly sensitive and low-cost pressure sensors are key elements in advancing wearable or implantable measuring devices.
The present invention provides a flexible piezoresistive sensor that exhibits improved piezoresistive sensitivity over other conventional flexible sensors currently available. The sensor is based on 3D porous auxetic materials and conductive materials coating layers. The sensing mechanism is the piezoresistivity of the conductive coating. The auxetic materials provide the overall sensing environment, and the unique auxetic properties enable high sensor sensitivity and larger sensing range.
FSU researchers have developed thermally stable piezoelectric polymer foams (ferroelectrets) with high piezoelectric activity for sensing and actuation, with tailored morphology, cell structure and mechanical and electro-mechanical properties. These piezoelectric foams have extremely high piezoelectric coefficients and very high thermal stability up to two orders of magnitude higher than other published results.
Thermoelectric (TE) materials generate energy in the presence of temperature differential by virtue of converting thermal energy to electrical energy. Combination of different semiconductors are the dominant thermoelectric materials. Currently all research on TE materials focus on inorganic substance and the applications of most TE materials are limited to high temperature regime (> 200 oC) to achieve meaningful figure of merit, which restricts application area. In this technology, COC ferroelectrets can harvest thermal energy operated at low temperature with high figure of merit.
Commercially available ferroelectrets are based on porous polypropylene films which has been applied in various devices, i.e., audio devices as microphones, force sensors, actuators and respiration detectors. However, these devices lack sufficient thermal and UV stability. Our foams overcome these limitations.
At FSU, we have developed a breakthrough process for scalable and low-cost functionalization of carbon nanotubes with tailored functionality. A provisional patent application was filed in October 2017. This technology enables the preparation of highly concentrated CNT ink for 3-D printing and printed electronics and sensors. As an example, while typical CNT ink has a CNT content < 0.5 wt%, our ink concentration can be tuned at will and can reach as high as 10 wt%. Such flexibility allows for our high quality printing process and superior device performance. This superior performance is characterized by a gauge factor (GR) that can reach ~3000; one to two orders of magnitude higher than any printed strain sensor from any other inks in the world. We have further demonstrated that our devices can be used as sensors to detect human motion. We strongly believe this technology will revolutionize printed electronics and sensors.