Dear all,
I encountered some peaks (right above 2000 cm-1 as seen in the picture attached) that I can't explain while analysing my multiwalled carbon nanotubes (MWCNTs) using FTIR, Perkins Elmer via the ATR method. I have conducted the readings on 4 separate occasions with similar results. According to some of the papers I've come across, none of them seem to have observed these peaks (I have attached one of the papers as an example). I've tried diluting the MWCNTs to 1% in water but it didn't appear to help either. Would anyone be able to explain how or why these peaks could be there? I would appreciate any words of advice you may have for me as this is fairly new to me.
Kindly find some of the other details as stated. My MWCNTs were purchased from Sigma Aldrich (Cat. no: 698849) with >98% carbon basis with an O.D. × L 6-13 nm × 2.5-20 μm early last year (Jan 2020). The MWCNTs viewed in the picture was used directly as purchased without any treatment (to serve as a control) and directly loaded onto the designated surface. A scanning range of 4000-400 cm-1 was used with a scan number of 16.
Hi. I suggest the following article that I hope could be help you:
Article Effects on the Thermo-Mechanical and Crystallinity Propertie...
@Mike Hale Hi, thank you for your reply. How would I determine whether it's an artifact seeing as I have observed this on 4 separate occasions? I made sure to clean everything before each reading. I was informed that I should cover the surface of the diamond to analyse my MWCNTs, if that's what you meant by crystals.
@Aref Wazwaz Hi and thank you for sharing. The paper you referred to doesn't seem to have the peaks that I observed above 2000 cm-1.
You must have used single reflection ATR using diamond as a reflection element. Diamond has three characteristic absorption bands in the 2100-1900 cm-1 range. These bands are mostly compensated when you use usual samples, such as polystyrene, though usually not compensated completely. Because the absorption by your usual sample is so strong, these uncompensated diamond peaks are usually not noticeable. However, since your sample, MWCNT, has almost no IR absorptions, such uncompensated, weak bands from the ATR element becomes visible. Therefore, you might call those bands as an instrumental artifact.
Dear Prof. Hatsuo Ishida, thank you for your reply. That makes perfect sense. I've recently come across several other papers with similar peaks when viewing their MWCNTs from Sigma using FTIR as well. They made no mention of it but I suppose they labelled it as an artifact. It should be safe to state these peaks as artifacts in my thesis, right? I've observed the same peaks in my functionalised MWCNTs as well so, I used that as an indication that my MWCNTs is still present.
- Badges
- Science topic
- Similar topics
- Physics
- Condensed Matter Physics
- Solid State Physics
- PEAKS