Photocatalytic reduction of dinitrogen to ammonia

The fixation of dinitrogen to ammonia via Haber's process is an energy intensive process and hence it is attractive to search for alternate pathways for the fixation of dinitrogen molecule under milder conditions. The photocatalytic reduction of dinitrogen to ammonia represents one such proposition. The discovery of this reaction by Schrauzer and Guth in 1977 prompted many workers to study this intriguing reaction and several studies have been reported in literature demonstrating the feasibility of this process. However, the low yields of ammonia obtained thus far, makes this process an uneconomical proposition. This article discusses the problems associated with the photoreduction of dinitrogen and gives an appraisal of the aspects concerning the photofixation of dinitrogen molecule on semiconductor systems.