Incorporated directly into a cell phone housing, the team's nanogenerator could harvest and convert vibration energy from a surface, such as the passenger seat of a moving vehicle, into power for the phone. "We believe this development could be a new solution for creating self-charged personal electronics," says Xudong Wang, an assistant professor of materials science and engineering at the University of Wisconsin-Madison.
Wang, his Ph.D. student Yanchao Mao and collaborators from Sun Yat-sen University in China, and the University of Minnesota Duluth described their device, a mesoporous piezoelectric nanogenerator, in the January 27, 2014, issue of the journal Advanced Energy Materials.
The nanogenerator takes advantage of a common piezoelectric polymer material called polyvinylidene fluoride, or PVDF. Piezoelectric materials can generate electricity from a mechanical force; conversely, they also can generate a mechanical strain from an applied electrical field.
Rather than relying on a strain or an electrical field, the researchers incorporated zinc oxide nanoparticles into a PVDF thin film to trigger formation of the piezoelectric phase that enables it to harvest vibration energy. Then, they etched the nanoparticles off the film; the resulting interconnected pores — called "mesopores" because of their size — cause the otherwise stiff material to behave somewhat like a sponge.
That sponge-like material is key to harvesting vibration energy. "The softer the material, the more sensitive it is to small vibrations," says Wang.
The nanogenerator itself includes thin electrode sheets on the front and back of the mesoporous polymer film, and the researchers can attach this soft, flexible film seamlessly to flat, rough or curvy surfaces, including human skin. In the case of a cell phone, it uses the phone's own weight to enhance its displacement and amplify its electrical output.
The nanogenerator could become an integrated part of an electronic device — for example, as its back panel or housing — and automatically harvest energy from ambient vibrations to power the device directly.
Wang says the simplicity of his team's design and fabrication process could scale well to larger manufacturing settings. "We can create tunable mechanical properties in the film," he says. "And also important is the design of the device. Because we can realize this structure, phone-powering cases or self-powered sensor systems might become possible."
—Renee Meiller, 608-262-2481, firstname.lastname@example.org
Xudong Wang | EurekAlert!
New high energy density automotive battery system from Fraunhofer IISB and international partners
25.08.2015 | Fraunhofer-Gesellschaft
New research may enhance display & LED lighting technology
10.08.2015 | University of Illinois College of Engineering
A University of Oklahoma astrophysicist and his Chinese collaborator have found two supermassive black holes in Markarian 231, the nearest quasar to Earth, using observations from NASA's Hubble Space Telescope.
The discovery of two supermassive black holes--one larger one and a second, smaller one--are evidence of a binary black hole and suggests that supermassive...
A team of European researchers have developed a model to simulate the impact of tsunamis generated by earthquakes and applied it to the Eastern Mediterranean. The results show how tsunami waves could hit and inundate coastal areas in southern Italy and Greece. The study is published today (27 August) in Ocean Science, an open access journal of the European Geosciences Union (EGU).
Though not as frequent as in the Pacific and Indian oceans, tsunamis also occur in the Mediterranean, mainly due to earthquakes generated when the African...
In mountainous regions earthquakes often cause strong landslides, which can be exacerbated by heavy rain. However, after an initial increase, the frequency of these mass wasting events, often enormous and dangerous, declines, in fact independently of meteorological events and aftershocks.
These new findings are presented by a German-Franco-Japanese team of geoscientists in the current issue of the journal Geology, under the lead of the GFZ...
Bacteria do not cease to amaze us with their survival strategies. A research team from the University of Basel's Biozentrum has now discovered how bacteria enter a sleep mode using a so-called FIC toxin. In the current issue of “Cell Reports”, the scientists describe the mechanism of action and also explain why their discovery provides new insights into the evolution of pathogens.
For many poisons there are antidotes which neutralize their toxic effect. Toxin-antitoxin systems in bacteria work in a similar manner: As long as a cell...
It comes when called, bringing care utensils with it and recording how they are used: Fraunhofer IPA is developing an intelligent care cart that provides care staff with physical and informational support in their day-to-day work. The scientists at Fraunhofer IPA have now completed a first prototype. In doing so, they are continuing in their efforts to improve working conditions in the care sector and are developing solutions designed to address the challenges of demographic change.
Technical assistance systems can improve the difficult working conditions in residential nursing homes and hospitals by helping the staff in their work and...
20.08.2015 | Event News
20.08.2015 | Event News
19.08.2015 | Event News
28.08.2015 | Physics and Astronomy
28.08.2015 | Health and Medicine
28.08.2015 | Life Sciences