Improving Cobalt as an Artificial Photosynthesis Catalyst
One of the most important processes in Nature is photosynthesis as it is what plant-life uses to create sugars. For a long time researchers have been trying to duplicate the process, but the most successful attempts have relied on expensive materials. Researchers at Argonne National Laboratory however have found a way to improve a catalyst that uses cobalt, a relatively cheap metal, and it could lead to other catalysts as well.
Platinum is among the rarer materials on Earth and that coupled with its many uses, including artificial photosynthesis, makes it quite expensive. Cobalt does not make as good a catalyst, but because of how cheap it is, it makes up for that deficit. Unfortunately cobalt-catalysts have had issues because it must be linked to a light-sensitive molecule, and the electrons excited by light can quickly lose their energy, before being put to use. What the researchers discovered though was a way to connect both the molecule and the cobalt atom to a larger organic ring. This separation prevents the electrons from falling to their ground state, and thus allows the photosynthesis process to continue longer.
Another advantage to using cobalt is that it is already well understood by researchers, so ways to improve its effectiveness are already known. Also the results from this research could be used to create catalysts using other, even cheaper metals, such as iron or nickel.
Source: Argonne National Laboratory