Catalysts on the Cusp of Coming Apart

 

A representation of multi-metal catalysts, which mimic photosynthetic reactions.
A representation of multi-metal catalysts, which mimic photosynthetic reactions. Image courtesy of Pacific Northwest National Laboratory

After years of research, Ted Betley’s work is on the verge of falling apart – in a good way. Thanks to a 2012 U.S. Department of Energy Office of Science Early Career Research Program Award, Ted is pushing the catalysts he’s building to the point of collapse.

Catalysts are molecular “machines” that speed chemical reactions. They are used by both Mother Nature and industry to turn raw materials into a host of desired products. Most industrial catalysts are stiff. Strong bonds link the atoms. Think of these bonds, called covalent bonds, as industrial-strength duct tape. While the bonds keep the catalyst together, they also make it difficult for the catalyst’s parts to move.

“They need to be on the edge,” said Ted. “Stability is the antithesis of reactions.”

So, Ted has created new catalysts with fewer covalent bonds. Instead, weaker bonds, more like bungee cords, keep the structure together. Improving the flexibility speeds the catalyst in creating the desired products.

The looser structure also frees up electrons that were “stuck” in the covalent bonds of the stiffer catalysts. These more readily available electrons help speed reactions. The trick to creating looser catalysts? Ted discovered that it is using multiple metals, not just one. These multi-metal catalysts are quick, and they drive complex reactions that use more than just one or two electrons.

Ted Betley's goal is to have his catalysts mimic photosynthesis, taking water and carbon dioxide to build complex sugars.

Ted Betley’s goal is to have his catalysts mimic photosynthesis, taking water and carbon dioxide to build complex sugars.

That’s important, since Ted’s goal is to have his catalysts mimic photosynthesis, which takes small molecules of water and carbon dioxide and builds complex sugars. The difference is that Ted’s catalysts take small molecules and turn them into biofuels. Creating fuels from renewable biological sources could reduce our nation’s reliance on fossil fuels.

“Our hypothesis of building in instability has definitely paid off,” said Ted. Others obviously agree, as his work has earned several honors, including a Presidential Early Career Award for Scientists and Engineers, the highest honor given by the U.S. government to those beginning their independent research careers.

Ted believes in flexibility in careers, too, not just catalysts. For example, Ted developed a program to show minority students how to design careers in basic research. A tenured professor of chemistry and chemical biology at Harvard University, Ted along with colleagues built a popular seminar program that is causing more students to consider research-based careers. “We wanted to break down the misconception of opportunities in science,” said Ted.

The Early Career Research Program Award has also given Ted the chance to engage intellectually with the catalysis research community. “A distinct advantage of receiving this award is being invited to the principal investigator meetings held by DOE’s Office of Science, Office of Basic Energy Sciences,” said Ted. “These intense events bring together an extraordinary collection of scientists.”

As to the future, this early career awardee is now delving into how the fundamental principles he’s discovering apply to other catalysts, not just those on the cusp of coming apart. By breaking bonds and better building biofuels, Ted is helping to improve our energy future, one reaction at a time.

The Office of Science is the single largest supporter of basic energy research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information please visit http://science.energy.gov.