Syntheses and thermal and chemical behaviors of tartrate and succinate intercalated Zn3Al and Zn2Cr layered double hydroxides

Tartrate and succinate anions have been intercalated in Zn3Al and Zn2Cr LDHs. The preparations using either coprecipitation, anion exchange, or reconstruction methods are described. In the case of tartrate-containing LDH, coprecipitation and reconstruction methods have proved to be very limited to lead to pure materials due to the particular reactivity of tartrate anions. Intercalation of both anions under room-temperature conditions gives rise to expanded LDH with similar basal spacing. Moderate thermal treatments lead in all cases to a reorientation of the anions in the interlayer domains associated with an interlayer contraction occurring around 80 degrees C. The structural characterization, the thermal evolution, and the chemical stability of all the phases are studied by PXRD, FTIR, TGA, and DTA.