What if a major heat-trapping greenhouse gas could be consumed to produce a valuable chemical that is in short supply? Chemists at the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have identified a catalyst—a substance that speeds up a chemical reaction—that may be able to do just that. This “bimetallic” catalyst, made of iron and nickel, drives the reaction of the greenhouse gas carbon dioxide and the energy-rich gas propane to produce propylene. Propylene is a chemical building block used in the manufacture of many everyday items, including batteries, automobile parts, and clothing and other textiles.