Nitrate reduction pathways on Cu single crystal surfaces: Effect of oxide and Cl−
| Autor: | Dennis P. Butcher, Andrew A. Gewirth |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Renewable Energy
Sustainability and the Environment Inorganic chemistry Oxide Infrared spectroscopy chemistry.chemical_element 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology Photochemistry Electrocatalyst 01 natural sciences Copper 0104 chemical sciences chemistry.chemical_compound chemistry Nitrate General Materials Science Partial oxidation Electrical and Electronic Engineering Nitrite 0210 nano-technology Single crystal |
| Zdroj: | Nano Energy. 29:457-465 |
| ISSN: | 2211-2855 |
| DOI: | 10.1016/j.nanoen.2016.06.024 |
| Popis: | The origin of different nitrate reduction activity between the (100), (111), and (110) faces of Cu is examined using vibrational spectroscopy and calculations. Shell isolated nanoparticle enhanced Raman spectroscopy (SHINERS) reveals a suite of intermediates from the nitrate reduction process on Cu(100), Cu(111), and Cu(110) including NO 2 − and HNO. All three faces show similar intermediates, suggesting the same mechanism is operative on all of them. Critical to the reduction pathway on the bare Cu surfaces is the reduction of nitrate to nitrite concomitant with partial oxidation of the Cu surface. This priming action facilitates nitrate reduction and reduces overpotentials, particularly on the Cu(111) and Cu(110) faces, which are more susceptible to oxidation. Decoration of the surfaces with Cl − suppresses nitrate reduction, resulting in higher overpotentials and lower current density. NH 3 is observed by SHINERS as a direct nitrate reduction product in the presence of Cl − , rather than NO x species observed on the bare Cu surfaces, indicating a reaction pathway unique from the bare, undecorated surface. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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