Synthesis of Porous Basic Magnesium Carbonate Crystallographic Materials with Flower-Like Structure
The porous basic magnesium carbonate (Mg5(CO3)4(OH)2.4H2O) crystal crystallographic materials with flower-like structure were prepared successfully by homogeneous precipitation method. Magnesium chloride hexahydrate (MgCl2.6H2O) and urea (CO(NH2)2) wereused as reaction materials. The experimental equipment was held at 100°C for 8 h. Phase and morphology of the product were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The formation mechanism of the product was investigated. It was found that the CO2 bubbles acted as porous templates. The growth and gathering of the CO2 bubbles induced the growth of the MgCO3.3H2O columnar crystals. Then the dissolution of the MgCO3.3H2O and the deposition of Mg5(CO3)4(OH)2.4H2O happened simultaneously. Finally the disappearance of MgCO3.3H2O brought about the formation of the porous structure.