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Indexed by:期刊论文

Date of Publication:2008-04-15

Journal:MATERIALS LETTERS

Included Journals:SCIE、EI

Volume:62

Issue:10-11

Page Number:1685-1688

ISSN No.:0167-577X

Key Words:spherical alpha-alumina; emulsion-based synthesis; sol-gel preparation; powder technology

Abstract:Unaggregated spherical a-alumina powder was prepared by the controlled hydrolysis of Al(OPri)(3) in a dilute solution consisting of CH3 (CH2)(6)CH2OH and CH3CN. Spherical AlOOH precursors crystallized to gamma-alumina at 1000 degrees C and converted to alpha-alumina at 1150 degrees C without intermediate phases. The particle morphology was retained after crystallization to alpha-alumina. The thermal behavior of spherical AlOOH precursors was characterized by differential thermal analysis (DTA). X-ray diffraction (XRD) was used to confirm the conversion of crystalline phase of alumina powder from amorphous to a-phase. Transmission electron microscopy (TEM) was used to investigate the morphologies and size of the precursors and products. The specific surface areas of alpha-alumina were measured by nitrogen adsorption technique. (c) 2007 Elsevier B.V. All rights reserved.