Grain growth and microstructural evolution of yttrium aluminum garnet nanocrystallites during calcination process

Journal Article · Fri Oct 15 04:00:00 EDT 2010 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2010.06.038· OSTI ID:22202828

Qin, Jie ^[1]; Yang, Ru ^[1]; Liu, Guoqiang; Li, Min ^[1]; Shi, Yongxi ^[2]

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1. State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, 100029 (China)
2. Colleges of Science, Beijing University of Chemical Technology, Beijing, 100029 (China)

An yttrium aluminum garnet (YAG) precursor precipitate was synthesized by urea method using yttria (Y{sub 2}O{sub 3}) and aluminum nitrate (Al(NO{sub 3}){sub 3}.9H{sub 2}O) as raw materials. The fresh wet precipitate was dried by supercritical carbon dioxide (CO{sub 2}) fluid and the resulting powder was calcined at temperatures from 600 to 1600 {sup o}C. Crystallization of YAG was detected at 800 {sup o}C, and completed at 900 {sup o}C. HRTEM images of the YAG product obtained above 900 {sup o}C revealed crystallographically specific oriented attachment along the [1 1 2] direction. Based on the observation of the particle morphology a possible growth mechanism of YAG nanoparticles was presented. The fast increase on the average crystallite size of YAG at temperatures from 900 to 1300 {sup o}C is attributed to the crystallographically specific oriented attachment growth process. As the growth process proceeds at higher temperatures, oriented attachment based growth becomes less important because of the increase on particle size, and the self-integration assisted by the Ostwald ripening becomes dominant.

• OSTI ID: 22202828
• Journal Information: Materials Research Bulletin, Journal Name: Materials Research Bulletin Journal Issue: 10 Vol. 45; ISSN MRBUAC; ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
ALUMINIUM
ALUMINIUM NITRATES
CARBON DIOXIDE
CRYSTALLIZATION
GRAIN GROWTH
MICROSTRUCTURE
NANOSTRUCTURES
NEODYMIUM LASERS
PARTICLE SIZE
PRECIPITATION
RAW MATERIALS
SYNTHESIS
TRANSMISSION ELECTRON MICROSCOPY
X-RAY DIFFRACTION
YTTRIUM OXIDES