X-ray diffraction and FTIR analysis on effect of time and temperature layered double hydroxides synthesis

Layered double hydroxides (LDHs) are materials of great scientific interest. They are used in numerous fields, such as in the pharmaceutical industry, environmental remediation, polymers, catalysis, among others, due to their anion exchange capacity. In this investigation, nine batches of LDHs were successfully produced by co-precipitation at low supersaturation. pH was maintained constant, and the aging stages of LDH were carried out at different temperatures: namely 30, 50, and 70 °C and times of 12, 18, and 24 h. The samples were characterized by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) techniques in order to evaluate the crystallinity and the presence of impurities in the materials obtained. The experimental results revealed that the structural characteristics of LDH (such as lattice parameters and the interlayer spacing) were not affected by temperature and/or time parameters in the aging synthesis step. The crystallinity and crystallite size of the LDHs increase with rising aging temperature and time.