New catalyst uses light to convert nitrogen to ammonia
Method could lead to more environmentally friendly fertilizer production
"My colleagues and I said, 'Let's do a crazy experiment,'" Kanatzidis said. "Let's excite the chalcogel with light, give it some nitrogen and see if the material will reduce the nitrogen to ammonia. To our surprise, we saw ammonia forming, and the ammonia got more and more intense over time."
The FeMoS co-factor in the chalcogel binds to nitrogen and reduces it by eight electrons, making two ammonia molecules and one hydrogen molecule, just as happens in nature.
After the early positive results, the Northwestern researchers conducted a number of control experiments that confirmed the ammonia produced did indeed come from the nitrogen and not some other source.
The chalcogel material is very robust. "This catalyst can go and go and go and still work," Kanatzidis said. "Nitrogenase in biological systems has to rebuild itself every six to eight hours."
The researchers do concede, however, that their catalyst is slower than nitrogenase, approximately 1,000 times slower.
"But nitrogenase had two or three billion years to evolve," Kanatzidis said. "We are happy that our material reduces nitrogen much like nitrogenase. It's a fantastic starting point. Now we are trying to figure out how this material works and how it can become faster. We've already made some progress in this direction."
Original publication
Abhishek Banerjee, Eric A. Margulies, Yongbo Zhang, Benjamin D. Yuhas, Yurina Shim and Michael R. Wasielewski; "Photochemical Nitrogen Conversion to Ammonia in Ambient Conditions with FeMoS-Chalcogels."; Journal of the American Chemical Society.
Original publication
Abhishek Banerjee, Eric A. Margulies, Yongbo Zhang, Benjamin D. Yuhas, Yurina Shim and Michael R. Wasielewski; "Photochemical Nitrogen Conversion to Ammonia in Ambient Conditions with FeMoS-Chalcogels."; Journal of the American Chemical Society.
Other news from the department science
Get the chemical industry in your inbox
From now on, don't miss a thing: Our newsletter for the chemical industry, analytics, lab technology and process engineering brings you up to date every Tuesday and Thursday. The latest industry news, product highlights and innovations - compact and easy to understand in your inbox. Researched by us so you don't have to.