Light‐Induced Ammonia Generation over Defective Carbon Nitride Modified with Pyrite
At a Glance
Section titled “At a Glance”| Metadata | Details |
|---|---|
| Publication Date | 2022-09-20 |
| Journal | Advanced Energy Materials |
| Authors | Judith Zander, Jana Timm, Morten Weiß, Roland Marschall |
| Institutions | University of Bayreuth |
| Citations | 52 |
Abstract
Section titled “Abstract”Abstract Photocatalytic nitrogen fixation under ambient conditions is currently widely explored in an attempt to develop a sustainable alternative for the Haber-Bosch process. In this work, defect‐rich carbon nitride, one of the most investigated photocatalysts reported in literature for ammonia generation, is combined with earth‐abundant and bioinspired FeS 2 to improve the activity for ammonia production. By this combination, an activity enhancement of ≈400% compared to unmodified carbon nitride is achieved. The optimal FeS 2 loading is established to be 1 wt%, with ammonia yields of up to 800 µg L −1 after irradiation for 7 h. By detailed material characterization of the electronic and material properties of the composites before and after the photocatalytic reaction, it is revealed that NH 3 generation occurs not photocatalytically from N 2 , but via a light‐induced reduction of N-CN groups adjacent to nitrogen vacancies in the structure of defect‐rich carbon nitride. FeS 2 acts similar to a cocatalyst, enhancing the ammonia yield by π‐back‐donation from Fe‐centers to the imine nitrogen of the defect‐rich carbon nitride, thereby activating the structure and boosting the ammonia generation from cyano groups.