Although platinum is among the most expensive catalytic materials, the new catalyst contains only trace amounts of platinum, yet is robust and effective at low temperatures. Essentially, its structure is a series of small "clusters" comprising only a few atoms, each in a specific arrangement. Each cluster is composed of one or a few a platinum atoms surrounded by a mixture of oxygen, hydroxyl and potassium atoms and is "seated" on the standard aluminum or silica support.
The researchers say the advance is important in part because, through a combination of experiments and first-principles theory, the work reveals a new type of active site for a specific, very important chemical reaction. "Most of the time, people are happy to say, 'Well, we've found a material. It works for a given application,'" says Mavrikakis.
In this case, says Flytzani-Stephanopoulos, the team took the next step to determine how and why the catalyst works. "If we want to move to the next stage with cheaper materials that are doing the specific chemical transformations, we need to understand the fundamentals," she says.
|Contact: Maria Flytzani-Stephanopoulos|
University of Wisconsin-Madison