Tag Archives: Steve Dunn

Pop and rock music lead to better solar cells

A Nov. 6, 2013 news item on Nanowerk reveals that scientists at the Imperial College of London (UK) and Queen Mary University of London (UK),

Playing pop and rock music improves the performance of solar cells, according to new research from scientists at Queen Mary University of London and Imperial College London.

The high frequencies and pitch found in pop and rock music cause vibrations that enhanced energy generation in solar cells containing a cluster of ‘nanorods’, leading to a 40 per cent increase in efficiency of the solar cells.

The study has implications for improving energy generation from sunlight, particularly for the development of new, lower cost, printed solar cells.

The Nov. 6, 2013 Imperial College of London (ICL) news release, which originated the news item, gives more details about the research,

The researchers grew billions of tiny rods (nanorods) made from zinc oxide, then covered them with an active polymer to form a device that converts sunlight into electricity.

Using the special properties of the zinc oxide material, the team was able to show that sound levels as low as 75 decibels (equivalent to a typical roadside noise or a printer in an office) could significantly improve the solar cell performance.

“After investigating systems for converting vibrations into electricity this is a really exciting development that shows a similar set of physical properties can also enhance the performance of a photovoltaic,” said Dr Steve Dunn, Reader in Nanoscale Materials from Queen Mary’s School of Engineering and Materials Science.

Scientists had previously shown that applying pressure or strain to zinc oxide materials could result in voltage outputs, known as the piezoelectric effect. However, the effect of these piezoelectric voltages on solar cell efficiency had not received significant attention before.

“We thought the soundwaves, which produce random fluctuations, would cancel each other out and so didn’t expect to see any significant overall effect on the power output,” said James Durrant, Professor of Photochemistry at Imperial College London, who co-led the study.

“The key for us was that not only that the random fluctuations from the sound didn’t cancel each other out, but also that some frequencies of sound seemed really to amplify the solar cell output – so that the increase in power was a remarkably big effect considering how little sound energy we put in.”

“We tried playing music instead of dull flat sounds, as this helped us explore the effect of different pitches. The biggest difference we found was when we played pop music rather than classical, which we now realise is because our acoustic solar cells respond best to the higher pitched sounds present in pop music,” he concluded.

The discovery could be used to power devices that are exposed to acoustic vibrations, such as air conditioning units or within cars and other vehicles.

This is not the first time that music has been shown to affect properties at the nanoscale. A March 12, 2008 article by Anna Salleh for the Australian Broadcasting Corporation featured a researcher who tested nanowire growth by playing music (Note: Links have been removed),

Silicon nanowires grow more densely when blasted with Deep Purple than any other music tested, says an Australian researcher.

But the exact potential of music in growing nanowires remains a little hazy.

David Parlevliet, a PhD student at Murdoch University in Perth, presented his findings at a recent Australian Research Council Nanotechnology Network symposium in Melbourne.

Parlevliet is testing nanowires for their ability to absorb sunlight in the hope of developing solar cells from them.

I’ve taken a look at the references cited by researchers in their paper and there is nothing from Parleviet listed, so, this seems to be one of those cases where more than one scientist is thinking along the similar lines, i.e., that sound might affect nanoscale structures in such a way as to improve solar cell efficiency.

Here’s a link to and a citation for the ICL/University of Queen Mary research paper,

Acoustic Enhancement of Polymer/ZnO Nanorod Photovoltaic Device Performance by Safa Shoaee, Joe Briscoe, James R. Durrant, Steve Dunn. Article first published online: 6 NOV 2013 DOI: 10.1002/adma.201303304
© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This paper is behind a paywall.