Thin cells for solar energy

A new type of very thin solar cell made from inexpensive materials has been invented by researchers at the Hahn Meitner Institute in Berlin, Germany, in collaboration with a colleague now at Portland State University, Oregon, USA. The new device will be much cheaper to make because it uses less expensive semiconductor materials than conventional solar cells. The researchers publish details of their invention in the Institute of Physics journal Semiconductor Science & Technology on 14 April 2003.

German physicists Rolf Koenenkamp, now at Portland State University, and former colleagues Katja Ernst and Abdelhak Belaidi have used a layer of titanium dioxide that is full of tiny pores to make a much more efficient device for harvesting the sun’s energy.

They formed an extremely thin layer of the light-sensitive cadmium telluride (CdTe) which forms the material for the solar cell on top of the porous titanium dioxide, which was itself supported on a sheet of glass. They connected electrical contacts to the back of this sandwich. When sunlight hits the cadmium telluride layer, the energy is converted into an electrical current which is tapped off via the electrical contacts. Any stray light bounces around inside the tiny pores in the titanium dioxide layer and is scattered back into the cadmium telluride layer, making the device more efficient. This boosts efficiency by a factor of fifty over a similar cell based on a non-porous support material.

The prototype solar cell produces a voltage of 0.67 V and a current of 8.9 milliamps per square centimetre when illuminated with just 100 milliwatts per square centimetre of light typical for a sunny day. The researchers also found that if they alloyed the CdTe with mercury they could boost the current to 15 milliamps. “Solar cells typically produce between 0.5 and 1 V voltage,” explains Koenenkamp, “In applications, several cells are connected in series to provide higher voltage as needed.”

There are a few wrinkles yet to be smoothed out in the prototype solar cell, but its properties offer the promise of renewable energy at much lower cost than current solid state devices. While the present device still uses hazardous or expensive materials, such as gold, cadmium and mercury in small amounts, the simple design principle could be used for other cell types, such as silicon and compound solar cells, says Koenenkamp.

Media Contact

Dianne Stilwell alfa

Weitere Informationen:

Alle Nachrichten aus der Kategorie: Power and Electrical Engineering

This topic covers issues related to energy generation, conversion, transportation and consumption and how the industry is addressing the challenge of energy efficiency in general.

innovations-report provides in-depth and informative reports and articles on subjects ranging from wind energy, fuel cell technology, solar energy, geothermal energy, petroleum, gas, nuclear engineering, alternative energy and energy efficiency to fusion, hydrogen and superconductor technologies.

Zurück zur Startseite

Kommentare (0)

Schreib Kommentar

Neueste Beiträge

An artificial cell on a chip

Researchers at the University of Basel have developed a precisely controllable system for mimicking biochemical reaction cascades in cells. Using microfluidic technology, they produce miniature polymeric reaction containers equipped with…

Specific and rapid expansion of blood vessels

Nature Communications: KIT researchers identify a new mechanism to control endothelial cell size and arterial caliber – basis for better treatment of heart infarct and stroke. Upon a heart infarct…

Climate change drives plants to extinction in the Black Forest in Germany

Climate change is leaving its mark on the bog complexes of the German Black Forest. Due to rising temperatures and longer dry periods, two plant species have already gone extinct…

By continuing to use the site, you agree to the use of cookies. more information

The cookie settings on this website are set to "allow cookies" to give you the best browsing experience possible. If you continue to use this website without changing your cookie settings or you click "Accept" below then you are consenting to this.