Researchers at Northwestern University's Institute for Catalysis in Energy Processing have discovered a new strategy for fabricating metal nanoparticles in catalysts which promises to enhance the selectivity and yield for a wide range of structure-sensitive catalytic reactions.
Because many industrial processes are dependent on catalysis, any advance in the design of catalysts can provide significant benefits to society.
Although catalytic supports are often selected for their high surface area or thermal, chemical, and mechanical stability, the support can also affect the selectivity and reactivity of the catalyst. (1-3) Classic catalytic work, for example that of Sinfelt and co-workers,(4-7) has shown that changing the support can dramatically alter the catalytic behavior.
Many theories have been proposed to explain the general role of supports, including sites at the metal−support interface,(8) particle size and surface-structure sensitivities,(9) ensemble-size sensitivity,(10) and strong metal−support interactions.(11, 12) The latter includes concepts such as intermetallic bond formation and charge transfer,(13, 14) diffusion of metal species between support and catalyst,(1, 15, 16) geometric decoration,(17-22) and other electronic effects.(23, 24) These insights have been gained from studies on model systems, largely single crystals. In the past, the various surface facets on high surface area supports have made these insights difficult to exploit, although the use of a support with both high surface area and controlled orientation may offer the opportunity to bridge this gap.