New Record in Third Generation Solar Cells
5 July 2008, 14:43
Categories: smt-energy-photovoltaic
Dye-sensitized solar cells (i.e., Grätzel Cells) imitate the way that plants and certain algae convert sunlight into energy. These third generation cells show great promise as a cheap alternative to expensive silicon solar cells. The cells are made up of a porous film of white titanium dioxide nanoparticles. The film is covered with a layer of dye, which is in contact with an electrolyte solution. When solar radiation hits the dye, it injects a negative charge in the pigment TiO2 nanoparticle and a positive charge into the electrolyte resulting in the conversion of sunlight into electrical energy.
Dye-sensitized cells are inexpensive, easy to produce and can withstand long exposure to light and heat compared with traditional silicon-based solar cells. However, their overall light conversion efficiency currently around 11%, about two times lower than silicon cell technologies. Additionally, dye-sensitized cell technology uses an electrolyte solution that is made up of volatile organic solvents and must be carefully sealed. This, along with the fact that the solvents permeate plastics, has precluded large-scale outdoor application and integration into flexible structures.
Now, researchers at the Chinese Academy of Sciences have achieved a record light conversion efficiency of 8.2% in solvent-free dye-sensitized solar cells. This breakthrough in efficiency without the use of volatile organic solvents will make it possible to pursue large scale, outdoor practical application of lightweight, inexpensive, flexible dye-sensitized solar films that are stable over long periods of light and heat exposure.
Posted by: The Editors
Permalink to this article
Previous: Nano On Mars
Next: Self-Assembly of Metals Achieved