Inorganic solar cells

Researchers at Berkeley Lab and the University of California, Berkeley, have developed what they claim are the first ultra-thin solar cells comprised entirely of inorganic nanocrystals that can be spun-cast from solution.

The dual nanocrystal solar cells are as cheap and easy to make as solar cells made from organic polymers and offer the added advantage of being stable in air because they contain no organic materials.

“Our colloidal inorganic nanocrystals share all of the primary advantages of organics — scalable and controlled synthesis, an ability to be processed in solution, and a decreased sensitivity to substitutional doping – while retaining the broadband absorption and superior transport properties of traditional photovoltaic semiconductors,” said Ilan Gur, a researcher in Berkeley Lab’s Materials Sciences Division.

In their labs, the researchers synthesised rod-shaped nanometre-sized crystals of two semiconductors, cadmium-selenide (CdSe) and cadmium-telluride (CdTe), then dissolved them in solution and spun-cast them onto a conductive glass substrate.