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Experts are soon reaching the potential of producing 3rd generation solar panels. Findings previously published will help engineers to develop a technology that limits the loss of energy from ‘hot electron’. Ultra-thin solar cells can soon become a concrete commercialized product.

According to researchers at Boston College, for the first time ‘hot electron’ recently considered very complex to capture can be extracted by using thin solar cells. This is portraying great potential for solar efficiency to escalate with these findings based on a report published in an Applied Physics Letters.

Actually, when solar cells capture light, electrons are freely produced in array of different energy states. The restrain to this technology is that to harness the energy generated from the electrons, they must be transferred to the conduction band found at the bottom. This transmission causes a drastic loss of energy generated by ‘hot’ electrons.

‘Hot electrons’ have been seen to be present in semiconductors and other devices. Yet the ‘hot carriers’ have had a negative effect on the devices used. High kinetic energy represented by ‘hot electrons’ has led to failure and degrading of apparatus. Although it is difficult to harness energy from ‘hot carriers’, it had since some time been proposed that this would become ‘3rd Generation’ solar devices and here they come.

At Boston College, Ferris Professor of Physics and co-author Michael J. Naughton, Evelyn J. and Robert A, say that the use of ultrathin solar cells, which are as thin as 30 nanometers, was necessary. This precision practically avoids ‘hot electrons’ to cool-down, disallowing the electrons to escape.

Professor of Physics Krzysztof Kempa, say that the key to harnessing the ‘hot electrons’ is to limit potential space for escape. He used the metaphor that a if ever a pot of boiling water were to be dropped in the middle of a swimming pool it would basically cause no alteration to the temperature at any of the edges. The heat would scatter and dissolve on the way to the edges. Yet, if the same hot pot of water was to be dropped in a sink with cold water, the temperature would increase. The reason is for this difference is that the sink is much smaller than the swimming pool.

This is how ‘hot electrons are captures. The electrons must be captured in less than picoseconds. Picoseconds are tantamount to less than a trillionth of a second.

Nanotechnology is certainly entering the field of energy efficiency. The ultrathin cells are fifty times as much thinner than contemporary cells that are being used. It also has a much higher absorption capacity. Yet, the technology can be improved even more with the use of nanowire structures. Ultra-thin cells harnessing energy from ‘hot electrons’, represent a major advancement in solar technology.

Reference:
Elusive ‘Hot’ Electrons Captured in Ultra-Thin Solar Cells