How to choose a catalyst
CAMBRIDGE, Mass. MIT researchers have found a new way to predict which materials will perform best as catalysts for oxygen reduction, a core process in metal air batteries and fuel cells, opening up the possibility of faster and more effective development of new high-efficiency, low-cost energy-storage technologies. Such catalysts are the crucial materials that govern the performance of fuel cells, as well as air-breathing batteries and other energy storage systems that are becoming increasingly important for everything from portable electronic devices to cars to the electric grid - where inexpensive storage is seen as key to increasing use of renewable but intermittent energy sources, such as solar or wind. But so far, selecting and testing such materials has essentially been a matter of trial and error, and most of the high-performing materials found have been rare and expensive, such as palladium and platinum. The new principle, by contrast, should allow rapid assessment of a range of alternative catalysts made of metal-oxide materials, many of which are made of inexpensive and abundant elements. The MIT researchers? analysis found that the effectiveness of different materials could be determined by the arrangement of electrons in the outer shells of their atoms, and the way surface metal ions bond to oxygen. The research - led by Yang Shao-Horn, an associate professor of mechanical engineering and materials science and engineering at MIT, and Hubert A. Gasteiger, a visiting professor at MIT and a chemistry professor at the Technische Universität München in Garching, Germany - was published June 13 .



