Abstract :
The surface electronic structures and compositions of Mo-based compounds oxides and nitrides.have been elucidated
using X-ray photoelectron spectroscopy XPS.. The Mo nitride samples were synthesized using the temperature-programmed
nitridation of a low surface area MoO3with NH3. The Mo oxides were also used to compare XPS results. No significant
change was observed in the surface electronic structure of core levels of Mo 3d, Mo 3p, N 1s, and O 1s for Mo nitrides after
the hydrogen reduction. A species with a Mo 3d5r2 binding energy of 228.4"0.2 eV from Mo nitrides was newly observed
and was calculated to be Mo1.3q. This value indicates that the absolute magnitude of charge transfer from Mo 4d states to N
2p states is 1.3 electrons per molybdenum in Mo nitrides. The binding energies of Mo 3d5r2 were shifted to lower ones
232.5ª230.0ª228.4 eV.as the oxides were transformed to nitride during nitridation Mo6qªMo4qªModq.. There
are two different regions nitride and oxide regions.present on the Mo nitride surface as shown from the deconvoluted Mo
3d peaks. For the Mo nitrides prepared in this study the nitride fraction was observed to be a majority on the surface. q1999
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