Record details

    High-temperature X-ray powder diffraction as a tool for characterization of smectites, layered double hydroxides, and their intercalates with porphyrins
    Bezdička, Petr
    Grygar, Tomáš
    Hradil, David
    Káfuňková, Eva
    Kovanda, František
    Lang, Kamil
    Píšková, Anna
    Večerníková, Eva
Publication type
    článek v periodiku
Source title - serial
    Applied Clay Science
    Roč. 49, č. 4
Thesaurus term
    layered double hydroxides
    thermal decomposition
Abstract (in english)
   We have analyzed expandable clay minerals and layered double hydroxides with different interlayer ions by high-temperature X-ray powder diffraction (HT-XRD) with comparison to thermal analysis (DTG/DTA) coupled with evolved gas analysis (EGA). We described in detail their thermal behaviour with emphasis to the differences among samples related to their crystallochemical characteristics. Porphyrin-intercalated smectites have a quite unique thermal behaviour as monitored by HT-XRD; the intercalates with tetrakis (1-methyl-4-pyridinio)porphyrin have a basal spacing of about 1.4 nm and are thermally stable up to ca. 600 °C. The resolution of the individual dehydration steps of smectites (from 2-layer hydrate via 1-layer hydrate to the anhydrous form) is much better in HT-XRD then in DTG/EGA curves. Layered double hydroxides (LDHs) have a varying thermal stability depending on their chemical composition and crystallinity. LDHs intercalated with porphyrin anions are thermally stable up to 35
   0-400 °C
    UK Praha, Přírodovědecká fakulta
Contributor code
    UK, PřF
Source format
Import date
    8. 8. 2012