Structural and morphological characterization of Mg0.8Al0.2(OH)2Cl0.2 hydrotalcite produced by mechanochemistry method

Abstract

Chlorine intercalated Mg–Al layered double hydroxides (Mg–Al–Cl–LDH) with a chemical formula Mg0.8Al0.2(OH)2Cl0.2 were successfully produced by the one-step mechanochemistry method and subsequent water washing followed by drying in oven for 1h at 80°C. The samples were characterized by X-ray diffraction (XRD), Fourier Transform Infrared spectroscopy (FT–IR), field emission scanning electron microscopy (FESEM), energy dispersive spectroscopy (EDS), elemental mapping analysis, transmission electron microscopy (TEM), X-ray fluorescence (XRF), and the differential thermogravimetric analysis (DTGA). Results revealed that the structural characteristics of Mg–Al–Cl–LDH were affected strongly by milling time. At the beginning of milling (up to 1h), Hydrotalcite (HT) and Brucite were the dominant phases, while the progressive mechanical activation was completed as milling time increased, which resulted in the formation of nanostructured Mg–Al–Cl–LDH. Based on XRD and FTIR data, Mg0.8Al0.2(OH)2Cl0.2 with high purity was obtained at 5h milling. The interlayer spacing of LDH is also strongly influenced by milling time so that it escalated from 7.737±0.001 to 8.005±0.002 (1–15h) and then decreased to 7.937±0.001 for 20h milled sample. Electron microscopic observation displayed that the final product had hexagonal platelet structure with lateral dimension of 20–100nm. Therefore, the synthesis of Mg0.8Al0.2(OH)2Cl0.2 via mechanochemistry owing to simplicity and versatility can be a promising candidate for use in catalyst carriers, drug delivery, and gene delivery.