Powering the Very Tiny

Nanoscale devices present a megascale bear of a problem when it comes to energy sources, especially when these devices are intended for implantation in the body.

Georgia Tech researcher Zhong Lin Wang (photo), who also holds positions at Peking University and the National Center for Nanoscience and Technology of China, and graduate student Jinhui Song are working on nanogenerators that produce current mechanically by bending and releasing zinc oxide nanowires, which are both piezoelectric and semiconducting. Interconnected arrays of millions of such wires could produce enough current to run nanoscale devices. Brought to fruition, this technology could resolve the dual issues of power supply bulk and toxicity.



Wang and Song grew arrays of zinc oxide nanowires and deflected individual wires using an atomic-force microscope (AFM) tip. This created a charge separation, positive on the stretched side and negative on the other. The charges were preserved because a Schottky barrier was formed between the AFM tip and the wire. Coupling between the semiconducting and piezoelectric properties resulted in the charging and discharging process when the tip scanned across the nanowire. When the tip lost contact with the wire, the strain was released and the wire vibrated through many cycles, but the researchers measured a current only at the instant of release. Similar tests on structures that were neither piezoelectric nor semiconducting indicated that the observed effect was truly a piezoelectric-induced discharge process.

SENSORS EXPO & CONFERENCE

Sensors 2019 Hits Silicon Valley June 25-27!

Join 7,000+ engineers this June in San Jose at the sensor industry’s biggest event! With 65+ Technical Sessions, 100+ Leading Speakers, 10 new and updated tracks, and 300+ Interactive Exhibits, there’s more opportunity than ever to connect with this booming industry and the technologies driving it. See thousands of the newest technologies in action, learn about the latest applications, and develop invaluable partnerships at the only event dedicated to sensors, connectivity, and systems.

Wang estimates that as much as 30% of the mechanical input can be converted to electrical energy for a single cycle of vibration. This would argue for harvesting the energy produced by the body and using it to power implanted medical devices. (http://tinyurl.com/q2k4e)

Suggested Articles

Accessible point-of-care devices could transform both agriculture and medicine.

Global magnetic sensor market is anticipated to reach $3,053.5 Million by 2028.

A unique power- and data-efficient system architecture for the always-on era.