Hamers and his team, including Di Zhu, Linghong Zhang and Rose E. Ruther, all of UW-Madison, turned to synthetic industrial diamond a cheap, gritty, versatile material as a potential new catalyst for the reduction process. Diamond, the Wisconsin team found, can facilitate the reduction of nitrogen to ammonia under ambient temperatures and pressures.
Like all chemical reactions, the reduction of nitrogen to ammonia involves moving electrons from one molecule to another. Using hydrogen-coated diamond illuminated by deep ultraviolet light, the Wisconsin team was able to induce a ready stream of electrons into water, which served as a reactant liquid that reduced nitrogen to ammonia under temperature and pressure conditions far more efficient than those required by traditional industrial methods.
"From a chemist's standpoint, nothing is more efficient than electrons in water," says Hamers, whose work is funded by the National Science Foundation. With the diamond catalyst, "the electrons are unconfined. They flow like lemmings to the sea."
While the method was demonstrated in the context of reducing nitrogen to a valuable agricultural product, the new diamond-centric approach is exciting, Hamers argues, because it can potentially fit a wide range of processes that require catalysis. "This is truly a different way of thinking about inducing reactions that may have more efficiency and applicability. We're doing this with diamond grit. It is infinitely reusable."
The technique devised by Hamers and his colleagues, he notes, still has kinks that need to be worked out to make it a viable alternative to traditional methods. The use of deep ultraviolet light, for example, is a limiting factor. Inducing reactions with visible light is a goal that would enhance the promise of the new technique for applications such as antipollution technology.
|Contact: Robert J. Hamers|
University of Wisconsin-Madison