The U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) together with the Joint Center for Artificial Photosynthesis (JCAP) have developed a unique artificial photosynthesis component for the creation of hydrogen from water.
According to Berkeley Lab, “The new JCAP photocathode construct consists of the semiconductor gallium phosphide and a molecular cobalt-containing hydrogen production catalyst from the cobaloxime class of compounds. As an absorber of visible light, gallium phosphide can make use of a greater number of available solar photons than semiconductors that absorb ultraviolet light, which means it is capable of producing significantly higher photocurrents and rates of fuel production. However, gallium phosphide can be notoriously unstable during photoelectrochemical operations.
“Moore and his colleagues found that coating the surface of gallium phosphide with a film of the polymer vinylpyridine alleviates the instability problem, and if the vinylpyridine is then chemically treated with the cobaloxime catalyst, hydrogen production is significantly boosted.”
So, in effect, this would allow platinum catalysts to be replaced with cheap and abundant metals, driving down the costs of hydrogen production. This invention also helps other researchers working on artificial photosynthesis with new tools and methods for producing the next class of solar-hydrogen generators.