Over at Nanowerk they have spotlighted research coming out Korea that has demonstrated the ability to use piezoelectric nanowires that can turn ∼100 decibel into enough energy to power very small electronic devices “self-powered sensors, e-papers, or body-implantable tiny devices” with the aim of powering larger devices when new nanomaterials are developed.
According to Dr. Jong Min Kim, Director of Frontier Research Lab, Samsung Advanced Institute of Technology (SAIT) and Sang-Woo Kim, a professor in the School of Advanced Materials Science & Engineering at Sungkyunkwan University, it is very difficult to use mechanical energy from sound in order to generate electrical energy using a conventional PZT-based bulk or thin film piezoelectric energy harvester.
The researchers overcame this obstacle by employing zinc oxide nanowires to serve as piezoelectric material sensitive enough to respond to sound energy. The nanogenerator device they made was able to transform ∼100 dB into an AC output voltage of 50mV.
The research was originally published in August 30, 2010, online issue of Advanced Materials.
The clearest application for this technology would be in cellular phones where one’s conversations could be used to power the device. However, since our speaking voice is around 60-70 dB and the device currently is not effective in generating power from sound less than 100 dB, it’s clear that more work has to be done.
The researchers believe the biggest obstacle they need to overcome is the limitations of zinc oxide, which they believe will help them design a device that will have improved piezoelectric performance.
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.