Research is currently active on the patented technology "Visible Light Photoreduction of CO2 Using Heterostructured Catalysts." The technology is available for licensing and/or further collaborative research from the U.S. Department of Energy’s National Energy Technology Laboratory.
In this invention, small semiconductor particles function as photocatalysts to promote various oxidation and reduction reactions under sunlight through the application of solar energy. Research data indicated a significant new finding for the photocatalytic reuse of carbon dioxide (CO2) or, simply, that the lower energy "tails" of the solar spectrum can be used for this application. As such, the results demonstrated an initial step toward creating more efficient photocatalysts for CO2 capture and reuse.
The inventors found that titanium dioxide (TiO2) is a promising material for application as a photocatalyst because it is efficient, relatively inexpensive, and environmentally friendly. However, the material’s widespread use has been hindered because it cannot be activated without ultraviolet (UV) light and UV light does not make up a significant amount of the solar spectrum. To overcome the hindrance, the inventors were able to shift the optical response of TiO2 from UV to the visible spectral range.
Specifically, researchers synthesized new heterostructured photocatalysts made from CdSe nanocrystals, TiO2nanocrystals, and Pt nanoparticles and demonstrated their activity toward the reduction of CO2 with H2O using only visible light. No ultraviolet light was required to initiate CO2 reduction reaction with H2O, and the value-added products of methanol, methane, and H2 were produced.
In summary, the photocatalytic reduction of CO2 uses readily available sunlight to convert CO2 into valuable chemicals, such as methanol or methane, in a carbon friendly manner.
U.S. Patent No: 8,986,511
Title: Visible Light Photoreduction of CO2 Using Heterostructured Catalysts
Inventors: Christopher Matranga, Congjun Wang, Robert Thompson
NETL Reference No: 09N-29