No chemist would think lithium was in short supply, Dr. Chirik said, but what happens if you put a lithium battery in every car? This is why chemistry needs to be ahead of the curve. We need to have adaptable solutions.
Despite the cost and relative scarcity of precious metals iridium, platinum, rhodium we rely on them to manufacture products from denim to beer, pharmaceuticals to fuel cells. The elements are used as catalysts, substances that kick off or enable chemical reactions.
Dr. Chiriks work involves dissolved catalysts, which are mixed into the end product. The molecules of the catalyst dissipate during the reaction. For instance, a solution containing platinum is used to make silicone emulsifiers, compounds that in turn feed products like makeup, cookware and glue. Tiny amounts of the expensive metal are scattered in all these things; your jeans, for instance, contain unrecoverable particles of platinum.
Were not about to run out of platinum, said Matthew Hartings, a chemist at American University in Washington, but this process spends that platinum in a nonsustainable way.
Dr. Chiriks chemistry essentially wraps an iron molecule in another, organic molecule called a ligand. The ligand alters the number of electrons available to form bonds. It also serves as a scaffold, giving the molecule shape. Geometry is really important in chemistry, Dr. Hartings said. Dr. Chiriks ligands help the iron to be in the right geometry to help these reactions along.
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