Monday, September 13, 2010

US Patent 7791157 - Qdot photovoltaic film

Optical coating are often formed on solar cells to reflect the portion of the spectrum which is not converted to electricity and thus avoid unwanted heating of the cells which reduces efficiency. This patent from Samsung teaches using a quantum dot film in place of such reflective coatings to convert the unusable portions of the spectrum to wavelengths that can be converted to electrical energy. Claim 1 reads:  

1. A solar cell comprising

a conductive substrate,

an energy conversion layer comprising a quantum dot compound and formed on at least one side of the substrate,

a light absorption layer, and

a counter electrode,

wherein the thickness of the energy conversion layer is about 20 nm to about 10 μm, and the solar cell is configured to generate an electric current upon absorbing light.