The in-efficiency of solar cells in converting the suns light into electricity is a key contributor to the high costs of solar energy, but new research into semiconductor nanostructures known as "nano flakes" may revolutionize the process and help improve the viability of Solar energy.



Details of the study by Martin Aagesen, a PhD from the NanoScience Center and the Niels Bohr Institute at University of Copenhagen were recently published in the nature nanotechnology. If his nanoflake solar cells meet expectations, they may be a huge step towards boosting the world’s exploitation of solar energy. Aagesen believes that the nano flakes have the potential to convert up to 30 per cent of the solar energy into electricity and that is roughly twice the amount that the average solar cell converts today.
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The finding was made during Aagesen’s work on his PhD when he found a new and un-tested material. “I discovered a perfect crystalline structure. That is a very rare sight. While being a perfect crystalline structure we could see that it also absorbed all light. It could become the perfect solar cell,” he said. The technology has the potential to decrease the solar cell production costs which rely on expensive semi-conducting silicon.

Aagesen is also director of the new established company SunFlake Inc. which is pursuing advance of the new solar cell.

The companies main focus is the development of an exceptionally efficient solar cell, based on new shapes of semiconductor nanostructures.

A large surface to volume ratio of the developed nanostructures as well as the texture of the covered surface allows a high absorption coefficient of the incoming sunlight without the use of an anti-reflective layer.

Control of nanostructures allows SunFlake to combine different semiconductor materials since requirements such as the need for a similar crystal structure as the carrier substrate is relaxed. The only purposes for the carrier substrate are to allow for the growth of the nanostructures and - when the solar cell is operating - act as a contact to the light absorbing nanostructures.

This circumstance will influence the cost of the final solar cell dramatically since only minute amounts of expensive ultra clean silicon is needed, compared to todays solar cells.

SunFlake is one of the first companies to use nano structures as the only active element in a solar cell. The prospect of achieving record high conversion efficiencies combined with a reduction in fabrication cost give SunFlake a strategic advantage on the fast growing competitive solar energy market.