Release Time:2019-03-10  Hits:

Indexed by: Journal Article

Date of Publication: 2008-04-15

Journal: MATERIALS LETTERS

Included Journals: EI、SCIE

Volume: 62

Issue: 10-11

Page Number: 1685-1688

ISSN: 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.