I use XRD to calculate the crystallinity, referring to the following formula：CrI=(I(110)-Iam)/I(110) (I(110) is the maximum strength of (110) planes,Iam is the diffraction intensity corresponding to 2 θ = 16 °）. But in my data, the diffraction peaks of (110) and (020) always recombine into one peak.Therefore, the result of deconvolution is always related to the factors of artificially selecting the peak position，which makes the calculation deviation of crystallinity larger.
Another formula ：CrI=Acrystal/Atotal （Acrystal and Atotal are the diffraction peak areas of the crystalline region and the total region, respectively）. But I don't know how to get the area of crystalline region, amorphous region and total region. Is there any calculation method and process that can be used in my data? If there are calculation details, it would be better. Thank you very much.
I have also characterized ATR and found that the crystallinity calculated by infrared intensity has exceeded 100%. I don't know what the problem is? The formula is：CrI=A1372/A2900
My raw data of XRD in various formats, deconvolution data, ATR raw data and images have all been uploaded. I hope you can help me. Thank you.
Dear Wang Chizhou many thanks for your interesting question. I would not call myself an expert in this field (we are inorganic chemists). So, all I can do is suggest to you a few relevant references which could help you in your analysis. Please have a look at
1. On the determination of crystallinity and cellulose content in plant fibres
Article On the determination of crystallinity and cellulose content ...
and
2. Physicochemical methods for determination of cellulose crystallinity
Article Physicochemical methods for determination of cellulose crystallinity
Both articles are freely available as public full texts on RG.-
Dear Wang Chizhou many thanks for your interesting question. I would not call myself an expert in this field (we are inorganic chemists). So, all I can do is suggest to you a few relevant references which could help you in your analysis. Please have a look at
1. On the determination of crystallinity and cellulose content in plant fibres
Article On the determination of crystallinity and cellulose content ...
and
2. Physicochemical methods for determination of cellulose crystallinity
Article Physicochemical methods for determination of cellulose crystallinity
Both articles are freely available as public full texts on RG.-
According to your xrd data, there is hardly diffraction peaks observed. this suggested your matetial was amorphous. Having said so, your material could possibly contain some low crystalline content due to LOD of your technique. Nonetheless, crystallinity of your sample was definitely below 1%, based on my experience.
Dear Wang Chizhou ,
There are several procedures to determine the crystallinity of cellulose.
The most frequent use is described the attached file:
Cellulose crystallinity index: measurement techniques and their impact on interpreting cellulase performance, Sunkyu Park, John O Baker, Michael E Himmel, Philip A Parilla, and David K Johnson, Park et al. Biotechnology for Biofuels 2010, 3:10.
Also, the following reference is useful for the whole discussion of the results:
OVERVIEW ON NATIVE CELLULOSE AND MICROCRYSTALLINE CELLULOSE I STRUCTURE STUDIED BY X-RAY DIFFRACTION (WAXD): COMPARISON BETWEEN MEASUREMENT TECHNIQUES, Nicoleta Terinte, Roger Ibbett and Kurt Christian Schuster, Lenzinger Berichte 89 (2011) 118-131.
I hope it helps somehow.
If for one particular area, check for one adopted special procedure; otherwise, the results will not be comparable.The Paper industry uses one procedure, the pharmaceutical industry another one.
Search specifically for the critical working area of your interest.
Best regards,
WNM
- Badges
- Science method
- Similar topics
- Methodology
- Crystallography
- X-ray Diffraction