Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tiny power generator runs on spit

04.04.2014

Saliva-powered micro-sized microbial fuel cells can produce minute amounts of energy sufficient to run on-chip applications, according to an international team of engineers.

Bruce E. Logan, Evan Pugh Professor and Kappe Professor of Environmental Engineering, Penn State, credited the idea to fellow researcher Justine E. Mink. "The idea was Justine's because she was thinking about sensors for such things as glucose monitoring for diabetics and she wondered if a mini microbial fuel cell could be used," Logan said. "There is a lot of organic stuff in saliva."


This is a micro microbial fuel cell with saliva input ports.

Credit: Bruce Logan, Penn State

Microbial fuel cells create energy when bacteria break down organic material producing a charge that is transferred to the anode. Logan, who has studied microbial fuel cells for more than ten years, usually looks to wastewater as a source for both the organic material and the bacteria to create either electricity or hydrogen, but these tiny machines are a bit different.

"By producing nearly 1 microwatt in power, this saliva-powered, micro-sized MFC already generates enough power to be directly used as an energy harvester in microelectronic applications," the researchers report in a recent issue of Nature Publishing Group's Asia Materials.

The researchers believe that the emergence of ultra-low-power chip-level biomedical electronics, devices able to operate at sub-microwatt power outputs, is becoming a reality. One possible application would be a tiny ovulation predictor based on the conductivity of a woman's saliva, which changes five days before ovulation. The device would measure the conductivity of the saliva and then use the saliva for power to send the reading to a nearby cell phone.

Biomedical devices using micro-sized microbial fuel cells would be portable and have their energy source available anywhere. However, saliva does not have the type of bacteria necessary for the fuel cells, and manufacturers would need to inoculate the devices with bacteria from the natural environment.

In the past, the smallest fuel cells have been two-chambered, but this micro version uses a single chamber with a graphene- rather than platinum-coated carbon cloth anode and an air cathode. Air cathodes have not been used before because if oxygen can get to the bacteria, they can breath oxygen and do not produce electricity.

"We have previously avoided using air cathodes in these systems to avoid oxygen contamination with closely spaced electrodes," said Logan. "However, these micro cells operate at micron distances between the electrodes. We don't fully understand why, but bottom line, they worked."

The anode is actually composed of carbon nanomaterial graphene. Other microbial fuel cells used graphene oxide, but the researchers showed that pure multi-layered graphene can serve as a suitable anode material.

While the researchers tested this mini microbial fuel cell using acetate and human saliva, it can use any liquid with sufficient organic material.

###

Justine E. Mink, recent Ph.D. recipient, King Abdullah University of Science and Technology, was first author of this paper. Also working on this project were Muhammad M. Hussain, assistant professor, and Ramy M. Qaisi, graduate student, KAUST.

KAUST supported this work.

A'ndrea Elyse Messer | EurekAlert!

More articles from Power and Electrical Engineering:

nachricht Piggyback battery for microchips: TU Graz researchers develop new battery concept
17.08.2016 | Technische Universität Graz

nachricht Lithium-ion batteries: Capacity might be increased by 6 times
09.08.2016 | Helmholtz-Zentrum Berlin für Materialien und Energie

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Streamlining accelerated computing for industry

PyFR code combines high accuracy with flexibility to resolve unsteady turbulence problems

Scientists and engineers striving to create the next machine-age marvel--whether it be a more aerodynamic rocket, a faster race car, or a higher-efficiency jet...

Im Focus: X-ray optics on a chip

Waveguides are widely used for filtering, confining, guiding, coupling or splitting beams of visible light. However, creating waveguides that could do the same for X-rays has posed tremendous challenges in fabrication, so they are still only in an early stage of development.

In the latest issue of Acta Crystallographica Section A: Foundations and Advances , Sarah Hoffmann-Urlaub and Tim Salditt report the fabrication and testing of...

Im Focus: Piggyback battery for microchips: TU Graz researchers develop new battery concept

Electrochemists at TU Graz have managed to use monocrystalline semiconductor silicon as an active storage electrode in lithium batteries. This enables an integrated power supply to be made for microchips with a rechargeable battery.

Small electrical gadgets, such as mobile phones, tablets or notebooks, are indispensable accompaniments of everyday life. Integrated circuits in the interiors...

Im Focus: UCI physicists confirm possible discovery of fifth force of nature

Light particle could be key to understanding dark matter in universe

Recent findings indicating the possible discovery of a previously unknown subatomic particle may be evidence of a fifth fundamental force of nature, according...

Im Focus: Wi-fi from lasers

White light from lasers demonstrates data speeds of up to 2 GB/s

A nanocrystalline material that rapidly makes white light out of blue light has been developed by KAUST researchers.

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

New Ideas for the Shipping Industry

24.08.2016 | Event News

A week of excellence: 22 of the world’s best computer scientists and mathematicians in Heidelberg

12.08.2016 | Event News

Towards the connected, automated and electrified automobiles: AMAA conference in Brussels

02.08.2016 | Event News

 
Latest News

New Ideas for the Shipping Industry

24.08.2016 | Event News

Lehigh engineer discovers a high-speed nano-avalanche

24.08.2016 | Physics and Astronomy

Streamlining accelerated computing for industry

24.08.2016 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>