Control of nitrogen activation ability by Co-Mo bimetallic nanoparticle catalysts prepared via sodium naphthalenide-reduction
| Autor: | Yasuhiro Niwa, Hitoshi Abe, Michikazu Hara, Yuki Tsuji, Masaaki Kitano, Kazuhisa Kishida, Toshiharu Yokoyama, Hideo Hosono, Kiya Ogasawara |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Thermal desorption spectroscopy
Inorganic chemistry Sodium naphthalenide chemistry.chemical_element 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Nitrogen Catalysis Dissociation (chemistry) 0104 chemical sciences X-ray absorption fine structure Ammonia production chemistry.chemical_compound chemistry Physical and Theoretical Chemistry 0210 nano-technology Bimetallic strip |
| Zdroj: | Journal of Catalysis. 364:31-39 |
| ISSN: | 0021-9517 |
| DOI: | 10.1016/j.jcat.2018.04.029 |
| Popis: | Co-Mo bimetallic nanoparticles (NPs) with various compositions were prepared on a CeO2 support (Co-Mo/CeO2) by sodium naphthalenide driven reduction. The Co-Mo/CeO2 catalyst exhibits much higher activity for ammonia synthesis than monometallic catalysts such as Co/CeO2 and Mo/CeO2, and the optimum activity is obtained at Co:Mo = 4:6. X-ray absorption fine structure (XAFS) analyses reveal that Co3Mo3N NPs are formed after ammonia synthesis reaction. Nitrogen temperature programmed desorption (N2-TPD) measurements indicate that the Co-Mo/CeO2 catalyst possesses a large number of nitrogen adsorption sites with an intermediate nitrogen adsorption energy between that of Co and Mo. Furthermore, nitrogen vacancy sites, which are active sites for N2 dissociation, are more easily formed on the Co-Mo/CeO2 catalyst than on bulk-type Co3Mo3N. As a consequence, the turnover frequency of the Co-Mo/CeO2 catalyst is much higher than that of bulk-type Co3Mo3N and is comparable to that of the efficient Ru/CeO2 catalyst. |
| Databáze: | OpenAIRE |
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