It is known for several decades, photovoltaic devices that exploit the sun's energy to convert into electricity used to provide a sustainable alternative - and potentially unlimited - the use of fossil fuels.
So why these solar technologies have they not been adopted more widely? Simply “because they are too expensive,' said Ji-Seon Kim, professor of Solid Physics at Imperial College of London, who with his colleagues has developed a technology that could help lowering prices of solar panels.
Scientists have described their new approach of making solar panels at low, but effective, cost in an article in the Journal of Chemical Physics.
“To capture a lot of light, you need to cover a large area solar panels, which comes at very high cost of inorganic photovoltaic, usually silicon,' says Professor Kim. The costs arise because traditional panels must be manufactured from crystals of high purity that require high temperatures and strict manufacturing conditions under vacuum.
A cheaper solution would be to design photovoltaic devices based on organic compounds - or solar cells that rely heavily on plastic.
The organic semiconductor materials, particularly polymers, may be dissolved in order to obtain a final ink. Then, it is require to make the impression of a very thin layer, of about 100 billionths meter thick, on a large area. 'Covering a vast area with plastic is much cheaper than doing it with silicon. Consequently, the cost per watt of electricity generation capacity has the potential to be much lower ' he added .
However, according to the team of scientists , the major difficulty has been to control the arrangement of polymer molecules in a thin layer . In their article, it describes a new method for such control, ' We have developed an advanced structural exploration technique that can determine the molecular envelope of two different polymers when they are mixed together.' By manipulating how the molecules of two polymers are assembled together, the researchers created paths ordered - or nanowires - along which the electrical charge can travel more easily. This allows the solar cell to generate more electricity.
'Our work highlights the importance of the precise arrangement of molecules in organic solar cell for it to work effectively,' concludes Prof. Kim, who expects that this type of solar cell enters the market within the next 5 to 10 years.
- By Greenshine New Energy; commercial solar lighting - solar parking lot lights - solar street lights