CHENG Pei, LI Xue, PEI Bingye, et al. Influence mechanism of anions on growth and morphology of Mg(OH)2 crystal[J]. CIESC Journal, 2017, (10): 3985-3992. DOI: 10.11949/j.issn.0438-1157.20170416.
DOI:
CHENG Pei, LI Xue, PEI Bingye, et al. Influence mechanism of anions on growth and morphology of Mg(OH)2 crystal[J]. CIESC Journal, 2017, (10): 3985-3992. DOI: 10.11949/j.issn.0438-1157.20170416.DOI:
Influence mechanism of anions on growth and morphology of Mg(OH)2 crystal
The magnesium hydroxide crystals were prepared by ammonia circulation method
using light burning powder
ammonium chloride
ammonium nitrate
ammonium acetate and ammonium sulfate as raw materials and ammonia gas as precipitant.X-ray diffraction (XRD) and scanning electron microscopy (SEM) have been employed to characterize these products.The effects of Cl-
NO3- and CH3COO- on the growth of (001) and (101) crystal planes of magnesium hydroxide crystals were calculated by the CASTEP module in the Materials Studio molecular simulation software.The results showed that magnesium hydroxide crystals with different morphologies were obtained by different magnesium salts.The larger the anionic electronegativity was
the smaller the effect on the crystal morphology.The (001) and (101) crystal face energy and population analysis of Mg (OH)2 crystals showed that the surface energy increased and Fermi energy decreased of (001) and (101) planes of the crystals with Cl-
NO3- and CH3COO-.New ionic bond with weak covalency was formed between anion and the (001) and (101) planes which affected the growth of the crystal plane.The theoretical calculations explained the formation of magnesium hydroxide crystals with different morphologies.