Hydrothermal Synthesis of Superfine Mg(OH)₂ Crystal

Abstract:

Hexagonal lamellar crystals with 200-500nm in diameter and 50-100nm in thickness and fibrous morphological crystals with 100-300nm in diameter and 10-30μm in lengths are synthesized in hydrothermal conditions using MgCl₂ and NaOH as raw materials in this paper. The particles size, morphology and crystal phase of the Mg (OH)₂ particles as obtained are characterized with scanning electron microscopy (SEM) and X-ray (XRD). The results indicated that precursor concentration, temperature and time play an important role in formation of Mg (OH)₂ crystals. The Mg (OH)₂ particles display hexagonal lamellar morphology, when MgCl₂ solution concentration is less than 1.5mol/L. Fibrous crystals are growing, when MgCl₂ solution concentration is more than 1.5mol/L. Raising temperature and extending time is in favor of formation of fibrous Mg (OH)₂ crystals. A mechanistic interpretation of formation of Mg (OH)₂ crystals in hydrothermal condition is postulated. The interpretation that fibrous crystal is converted from hexagonal crystal is proved.

• Periodical: Advanced Materials Research (Volumes 726-731)
• Pages: 662-667
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.726-731.662
• Online since: August 2013
• Authors: En De Wang*, Ming Gang Wu, Chao Shuai Li, Ye Kai Men, Jian Ming Xia
• Keywords: Fibrous Morphology, Hexagonal Lamellar Morphology, Hydrothermal Synthesis, Magnesium Hydroxide, Temperature

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