Spin-modified catalysis

نویسندگان

  • R Choudhary
  • B Balamurugan
  • R. Choudhary
  • P. Manchanda
  • A. Enders
  • B. Balamurugan
  • A. Kashyap
  • D. J. Sellmyer
  • E. C. H. Sykes
چکیده

First-principle calculations are used to explore the use of magnetic degrees of freedom in catalysis. We use the Vienna Ab-Initio Simulation Package to investigate both L1 0-ordered FePt and CoPt bulk materials and perform supercell calculations for FePt nanoclusters containing 43 atoms. As the catalytic activity of transition-metal elements and alloys involves individual d levels, magnetic alloying strongly affects the catalytic performance, because it leads to shifts in the local densities of states and to additional peaks due to magnetic-moment formation. The peak shift persists in nanoparticles but is surface-site specific and therefore depends on cluster size. Our research indicates that small modifications in stoichiometry and cluster size are a useful tool in the search for new catalysts.

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تاریخ انتشار 2015