According to United States physicist organization network recently reported that the United States national renewable energy Laboratory (NREL) developed a new type of quantum dot solar cells, when it was issued by the high energy region of the solar spectrum photon is active, the photographic currents of external quantum efficiency of up to 114%. Published on December 16 issue of the journal Science this latest study on laying a foundation for scientists developed the third generation solar cells.
When photons incident to the solar surface, some photons can trigger photosensitive material produce electron hole pair formed photographic currents, electron number and ratio of the number of incident photons are called external quantum efficiency of the photographic currents. To date, no solar panels in solar spectroscopy neiguangbo exposure, showing external quantum efficiency of more than 100%.
Now, the NREL team for the first time in the quantum dot solar cells achieved this. They are in a quantum dot solar cells laminated acquired 114% external quantum efficiency. The battery has less reflective coated glass (it contains a thin layer of transparent conductors), a layer of zinc oxide nano-structures, one treated layer of lead selenide quantum dots, and composed of a thin layer of gold used as electrodes.
Solar photons produce more than 100% external quantum efficiency based on containing a multiplier (MEG), with the help of this process, a single high-energy photon energy is absorbed fire multiple electron hole pair. NREL team for the first time in the photographic currents of quantum dot solar cells show a MEG, scientists through improving the conversion efficiency of solar cells. Study results show that simulate sunlight exposure, new quantum dot solar photoelectric conversion efficiency higher than 4.5%. At present, this solar cell is not yet optimal, and therefore its energy conversion efficiency is relatively low.
Compared with conventional solar cells, MEG in a quantum dot solar cells can improve battery theory of thermal energy efficiency 35%; quantum dot solar cells also use of cheap and high yield roll to roll manufacturing process together; another advantage is its very low manufacturing cost per unit area, scientists referred to as third generation (next generation) solar cells.
