Lowa State, Ames Lab Researcher Hunts For Green Catalysts

L. Keith Woo is searching for cleaner, greener chemical reactions. Woo, an Iowa State University professor of chemistry and an associate of the U.S. Department of Energy's Ames Laboratory, has studied catalysts and the chemical reactions they affect for more than 25 years. And these days, his focus is on green catalysis.

That, he said, is the search for catalysts that lead to more efficient chemical reactions. That could mean they promote reactions at lower pressures and temperatures. Or it could mean they promote reactions that create less waste. Or it could mean finding safer, cleaner alternatives to toxic or hazardous conditions, such as using water in place of organic solvents.

"We're trying to design, discover and optimize materials that will produce chemical reactions in a way that the energy barrier is lowered," Woo said. "We're doing fundamental, basic catalytic work."

And much of that work is inspired by biology.

In one project, Woo and his research group are studying how iron porphyrins (the heme in the hemoglobin of red blood cells) can be used for various catalytic applications. Iron porphyrins are the active sites in a variety of the enzymes that create reactions and processes within a cell. Most of the iron porphyrin reactions involve oxidation and electron transfer reactions.

Because the iron porphyrins of biology have evolved into highly specialized catalysts, Woo and his research group are studying how they can be used synthetically with the goal of developing catalysts that influence a broader range of reactions.

"We've found porphyrins are capable of doing many reactions – often as well, or better, or cheaper than other catalysts," Woo said.