Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species

doi:https://doi.org/10.1021/j100320a041

Title: Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species

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Abstract

The effects of molybdenum addition to silica-supported rhodium have been studied by using infrared spectroscopy. A new rhodium dicarbonyl species with characteristic bands at 2110 and 2052 cm/sup -1/ was observed during treatment of Rh-Mo/SiO/sub 2/ catalysts with CO at room temperature following reaction of nitric oxide with CO over the catalysts at 200/sup 0/C. These bands are approximately 15 cm/sup -1/ higher than the bands usually reported for the rhodium dicarbonyl species. Infrared spectra show the presence of both rhodium dicarbonyl species simultaneously which suggests that the new species is not a shifted form of the lower frequency species, but rather a new entity. It is also observed that the new species is much less stable in a reducing atmosphere than the lower frequency species. It is therefore proposed that the new dicarbonyl species contains a more oxidized form of rhodium than the traditional Rh/sup +/ dicarbonyl species and that the addition of molybdenum promotes this increased oxidation of the Rh surface sites.

Authors:: Wardinsky, M D; Hecker, W C

Publication Date:: 1988-05-05

Research Org.:: Brigham Young Univ., Provo, UT (USA)

OSTI Identifier:: 6862055

Resource Type:: Journal Article

Journal Name:: J. Phys. Chem.; (United States)

Additional Journal Information:: Journal Volume: 92:9

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; 33 ADVANCED PROPULSION SYSTEMS; MOLYBDENUM OXIDES; CATALYTIC EFFECTS; RHODIUM OXIDES; SILICA; ABSORPTION SPECTROSCOPY; CARBON MONOXIDE; CARBONYLS; CATALYSIS; CATALYSTS; EXPERIMENTAL DATA; INFRARED SPECTRA; NITRIC OXIDE; RHODIUM COMPOUNDS; VALENCE; CARBON COMPOUNDS; CARBON OXIDES; CHALCOGENIDES; DATA; INFORMATION; MINERALS; MOLYBDENUM COMPOUNDS; NITROGEN COMPOUNDS; NITROGEN OXIDES; NUMERICAL DATA; OXIDE MINERALS; OXIDES; OXYGEN COMPOUNDS; REFRACTORY METAL COMPOUNDS; SILICON COMPOUNDS; SILICON OXIDES; SPECTRA; SPECTROSCOPY; TRANSITION ELEMENT COMPOUNDS; 400201* - Chemical & Physicochemical Properties; 330701 - Emission Control- Nitrogen Oxides

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                    Wardinsky, M D, and Hecker, W C. Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species.  United States: N. p., 1988. 
        Web.  doi:10.1021/j100320a041.

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                    Wardinsky, M D, & Hecker, W C. Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species.  United States.  https://doi.org/10.1021/j100320a041

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                    Wardinsky, M D, and Hecker, W C. Thu .  
        "Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species".  United States.  https://doi.org/10.1021/j100320a041.

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@article{osti_6862055,

  title        = {Effect of molybdenum addition to Rh/SiO/sub 2/ catalysts: appearance of a second rhodium dicarbonyl species},

  author       = {Wardinsky, M D and Hecker, W C},

  abstractNote = {The effects of molybdenum addition to silica-supported rhodium have been studied by using infrared spectroscopy. A new rhodium dicarbonyl species with characteristic bands at 2110 and 2052 cm/sup -1/ was observed during treatment of Rh-Mo/SiO/sub 2/ catalysts with CO at room temperature following reaction of nitric oxide with CO over the catalysts at 200/sup 0/C. These bands are approximately 15 cm/sup -1/ higher than the bands usually reported for the rhodium dicarbonyl species. Infrared spectra show the presence of both rhodium dicarbonyl species simultaneously which suggests that the new species is not a shifted form of the lower frequency species, but rather a new entity. It is also observed that the new species is much less stable in a reducing atmosphere than the lower frequency species. It is therefore proposed that the new dicarbonyl species contains a more oxidized form of rhodium than the traditional Rh/sup +/ dicarbonyl species and that the addition of molybdenum promotes this increased oxidation of the Rh surface sites.},

  doi          = {10.1021/j100320a041},

  url          = {https://www.osti.gov/biblio/6862055},
  journal      = {J. Phys. Chem.; (United States)},
number       = ,

  volume       = 92:9,

  place        = {United States},

  year         = {1988},

  month        = {5}

}

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