Ammonia (NH3) is one of the most widely produced chemicals, with a global output of 170 megatons per year. It is the key ingredient in the production of fertilizers, and thus plays a critical role in sustaining the world's population. However, more than 1 percent of global energy is consumed by the production of ammonia, which involves the reaction of dinitrogen (N2) from air and dihydrogen (H2), via the Haber-Bosch process.