| Autor: |
Senanayake, Sanjaya D, Ramírez, Pedro J, Waluyo, Iradwikanari, Kundu, Shankhamala, Mudiyanselage, Kumudu, Liu, Zongyuan, Liu, Zhi, Axnanda, Stephanus, Stacchiola, Dario J, Evans, Jaime, Rodriguez, José A |
| Rok vydání: |
2016 |
| Předmět: |
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| Zdroj: |
The Journal of Physical Chemistry C, vol 120, iss 3 |
| Popis: |
The role of the interface between a metal and oxide (CeOx-Cu and ZnO-Cu) is critical to the production of methanol through the hydrogenation of CO2 (CO2 + 3H2 → CH3OH + H2O). The deposition of nanoparticles of CeOx or ZnO on Cu(111),oxi < 0.3 monolayer, produces highly active catalysts for methanol synthesis. The catalytic activity of these systems increases in the sequence: Cu(111) < ZnO/Cu(111) < CeOx/Cu(111). The apparent activation energy for the CO2 → CH3OH conversion decreases from 25 kcal/mol on Cu(111) to 16 kcal/mol on ZnO/Cu(111) and 13 kcal/mol on CeOx/Cu(111). The surface chemistry of the highly active CeOx-Cu(111) interface was investigated using ambient pressure X-ray photoemission spectroscopy (AP-XPS) and infrared reflection absorption spectroscopy (AP-IRRAS). Both techniques point to the formation of formates (HCOO-) and carboxylates (CO2δ-) during the reaction. Our results show an active state of the catalyst rich in Ce3+ sites which stabilize a CO2δ- species that is an essential intermediate for the production of methanol. The inverse oxide/metal configuration favors strong metal-oxide interactions and makes possible reaction channels not seen in conventional metal/oxide catalysts. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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