A different class

A new class of catalysts created at Argonne National Laboratory may help engineers overcome some of the hurdles that have inhibited the production of hydrogen for use in fuel cells.

Argonne chemist Michael Krumpelt and his colleagues in Argonne's Chemical Engineering Division used "single-site" catalysts based on ceria or lanthanum chromite doped with platinum or ruthenium to boost hydrogen production at lower temperatures during reforming. 'We've made significant progress in bringing the rate of reaction to where applications require it to be,' Krumpelt said.

Most hydrogen produced industrially is created through steam reforming. In this process, a nickel-based catalyst is used to react natural gas with steam to produce pure hydrogen and carbon dioxide.

According to Argonne, these nickel catalysts typically consist of metal grains tens of thousands of atoms in diameter that speckle the surface of metal oxide substrates. Conversely, the new catalysts that Krumpelt developed consist of single atomic sites imbedded in an oxide matrix. Because some reforming processes tend to clog much of the larger catalysts with carbon or sulphur by-products, smaller catalysts process the fuel much more efficiently and can produce more hydrogen at lower temperatures.