Please use this identifier to cite or link to this item:
https://scholarbank.nus.edu.sg/handle/10635/96107
DC Field | Value | |
---|---|---|
dc.title | Copper Sites in Copper-Exchanged ZSM-5 for CO Activation and Methanol Synthesis: XPS and FTIR Studies | |
dc.contributor.author | Chen, H.Y. | |
dc.contributor.author | Chen, L. | |
dc.contributor.author | Lin, J. | |
dc.contributor.author | Tan, K.L. | |
dc.contributor.author | Li, J. | |
dc.date.accessioned | 2014-10-16T09:19:33Z | |
dc.date.available | 2014-10-16T09:19:33Z | |
dc.date.issued | 1997-03-26 | |
dc.identifier.citation | Chen, H.Y.,Chen, L.,Lin, J.,Tan, K.L.,Li, J. (1997-03-26). Copper Sites in Copper-Exchanged ZSM-5 for CO Activation and Methanol Synthesis: XPS and FTIR Studies. Inorganic Chemistry 36 (7) : 1417-1423. ScholarBank@NUS Repository. | |
dc.identifier.issn | 00201669 | |
dc.identifier.uri | http://scholarbank.nus.edu.sg/handle/10635/96107 | |
dc.description.abstract | Cu-ZSM-5 samples with various Cu+/Cu2+ ratios have been successfully prepared in three different methods and studied by XPS and FTIR. Cu+ ions are found, by XPS, to mainly exist in the samples prepared by solution ion exchange and microwave solid-state reaction exchange. On the basis of the chemical shift of the Al 2p core level to a higher binding energy [Al(species II)], with the atomic ratio of Cu+/Al(species II) being approximately one, and the vanishing of the IR band at 3640 cm-1 due to copper exchange, it is suggested that Cu+ ions locate in the open channels of the ZSM-5 framework and bind to mixed (Si- and Al-) bridged oxide ion. From the ZSM-5 pore structure consideration, as well as from the observed decrease in the IR intensity ratio of bands 550/450 cm-1 with enhanced Cu2+ loading, it is also suggested that Cu2+ ions are a predominant Cu species in solid-state reaction exchanged Cu-ZSM-5 samples and exist as a CuO cluster in small cages as well as in open channels. The IR bands at 907 and 964 cm-1 are identified as zeolite asymmetric internal vibration perturbed by exchanged Cu2+ and Cu+ ions, respectively. Cu ions in Cu-ZSM-5 samples can be reduced to Cu0 by CO adsorption at room temperature. The IR bands at 2128, 2158, and 2176 cm-1 are observable and ascribed to the CO adsorbed on Cu0, Cu+, and Cu2+ sites, respectively. Methanol formation from syngas over Cu-ZSM-5 is observed at 250 °C and 2 MPa. | |
dc.source | Scopus | |
dc.type | Article | |
dc.contributor.department | PHYSICS | |
dc.description.sourcetitle | Inorganic Chemistry | |
dc.description.volume | 36 | |
dc.description.issue | 7 | |
dc.description.page | 1417-1423 | |
dc.description.coden | INOCA | |
dc.identifier.isiut | NOT_IN_WOS | |
Appears in Collections: | Staff Publications |
Show simple item record
Files in This Item:
There are no files associated with this item.
Google ScholarTM
Check
Items in DSpace are protected by copyright, with all rights reserved, unless otherwise indicated.