Crystallization behaviors of hexagonal nanoplatelet MgAl–CO 3 layered double hydroxide

Abstract

Hexagonal nanoplatelets of layered double hydroxide containing Mg 2+ and Al 3+ cations and CO 3 2 − anion (MgAl–CO 3-LDH) were successfully synthesized via an ethylenediamine-assisted hydrothermal route. The obtained samples were characterized by X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectrometry, scanning electron microscopy (SEM), transmission electron microscope (TEM), and UV–vis diffuse reflectance spectrum, respectively. The results show that ethylenediamine not only inhibits impurity phases generated in the synthesis of MgAl–CO 3-LDH but also can effectively control the crystal size of MgAl–CO 3-LDH in the range of 50−100 nm. In particular, a possible formation mechanism of hexagonal nanoplatelet MgAl–CO 3-LDH is proposed. The present work develops a simple and mild route to crystallize MgAl–CO 3-LDH with hexagonal nanoplatelet morphology, which is a key engineering step toward its potential size-dependent applications.