Sound DeviceThursday 4th September 2014
Using alternative ways for charging mobile devices is a major aim for many developers - there are so many devices that they consume plenty of electricity just to keep them charged and useful. Renewable energy solutions are continually being launched onto the market, now there is a very different way to charge your smart phon, and it also renewable.
Charging a mobile phones with sound - it could become a reality, according to a new collaboration between scientists from Queen Mary University of London (QMUL) and Microsoft.
Last year, in research with Imperial College London Dr Joe Briscoe and Dr Steve Dunn from QMUL’s School of Engineering and Materials Science found that playing pop and rock music improves the performance of solar cells.
Developing this research further, Microsoft worked with the QMUL team to create an energy-harvesting prototype (a nanogenerator) that could be used to charge a mobile phone using everyday background noise – such as traffic, music, and our own voices.
The team used the key properties of zinc oxide, a material that when squashed or stretched creates a voltage by converting energy from motion into electrical energy, in the form of nanorods.
The nanorods can be coated onto various surfaces in different locations making the energy harvesting quite versatile. When this surface is squashed or stretched, the nanorods then generate a high voltage.
The nanorods respond to vibration and movement created by everyday sound, such as our voices. Electrical contacts on both sides of the rods are then used to harvest the voltage to charge a phone.
In order to make it possible to produce these nanogenerators at scale, the scientists found innovative ways to cut costs in the production process.
Firstly, they developed a process whereby they could spray on the nanorod chemicals – almost like nanorod graffiti – to cover a plastic sheet in a layer of zinc oxide. When put into a mixture of chemicals and heated to just 90°C, the nanorods grew all over the surface of the sheet.
Secondly, gold is traditionally used as an electrical contact but the team were able to produce a method of using cheap and cheerful aluminum foil instead.
The ultimate device was the same size as a Nokia Lumia 925 and generates five volts, which is enough to charge a phone.
In he future it may not be a case of frowning angrily at the person on the train shouting down the phone, but at the man shouting at his phone!
Watch this video about harnessing energy from sound:
<iframe width="560" height="315" src="//www.youtube.com/embed/nmn3LNAiNBA?rel=0" frameborder="0" allowfullscreen>iframe>
Source: Queen Mary University of London
Picture: By Peter Drier (Flickr) reproduced under CCL.
Thursday 4th September 2014