I want to identify C-C and C=C peak in XPS spectra. Most of the references say that two peak can appears same position. Another questions is C-NH2 and C-NH-C peaks are also can be distinguish or not clearly in XPS spectroscopy method. I hope I will get your suggestion. Thanks you all.
http://xpssimplified.com/elements/carbon.php
http://srdata.nist.gov/xps/
Regards,
Dmitry
Please go through the attached ppt. I hope it will help you. I prepared that for XPS analysis.
Meanwhile you went probably went through the databases and noticed that you will not really be able to distinguish the mentioned species. In the case of C-C and C=C it is difficult to tell the BE because you would need an independent charging reference. (I assume we are talking about insulating materials according the structural features.) If you have both in comparable concentrations you might notice a large FWHM of your C-C/C=C signal. However, if you also have carbon in C-N or in higher oxidized structures it can also broaden the C-C/C=C component.
Regarding the C-NH2 and C-NH-C structures: You will not be able to distinguish them in the N1s spectrum. But if you calculate the ratio between the C-N component in the C1s with the corresponding component in the N1s (adjust by elemental concentrations) you might be able to decide which of the species you have.
Besides, derivatization reactions can help in both cases. Bromine adds to C=C and you can determine the Br concentration. For the amines you have various options. You can use some aldehyde (e.g. trifluormethyl benzaldehyde) which will react only with the C-NH2. Then the fluorine concentration tells you the C-NH2 conentration. Trifluoroacetic anhydride reacts with both. But the BE of the carbon atoms bonded to the N will shift to higher values and you will be able to quantify them and compare them with the N1s data as explained above.
- Badges
- Science topic
- Similar topics
- Automotive Engineering
- Machines