Raman spectroscopy of nanophase TiO sub 2

Journal Article · Fri Sep 01 04:00:00 EDT 1989 · Journal of Materials Research; (USA)

DOI:https://doi.org/10.1557/JMR.1989.1246· OSTI ID:5486459

Melendres, C A; Narayanasamy, A; Maroni, V A; Siegel, R W ^[1]

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1. Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439-4837 (US)

Raman spectra are reported for consolidated nanophase TiO{sub 2} particles in their as-compacted state and after annealing at a variety of temperatures up to 1273 K. The Raman-active bands normally observed for the rutile form of TiO{sub 2} were present in as-compacted samples having average grain sizes in the range from about 10 to 100 nm. However, significant broadening of these bands was found, which was uncorrelated with initial grain size, but not necessarily with other synthesis-related factors. This broadening decreased upon isochronal annealing at elevated temperatures in air. Based upon these observation, it is concluded that nanophase TiO{sub 2} in the as-consolidated state contains significant defect concentrations within the rutile grains and that these intragrain defects and the grain-boundary regions as well have local atomic structures with the rutile symmetry, albeit with some short-range displacements. Some sporadic sample regions containing small amounts ({lt}5) of the anatase form of TiO{sub 2} were also found; these traces of anatase transformed to rutile upon annealing in air at temperatures above 883 K.

• Research Organization: Argonne National Laboratory (ANL), Argonne, IL
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 5486459
• Journal Information: Journal of Materials Research; (USA), Journal Name: Journal of Materials Research; (USA) Vol. 4:5; ISSN JMREE; ISSN 0884-2914
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360204* -- Ceramics
Cermets
& Refractories-- Physical Properties
ANNEALING
CHALCOGENIDES
CHEMICAL REACTIONS
CRYSTAL STRUCTURE
GRAIN BOUNDARIES
HEAT TREATMENTS
HIGH TEMPERATURE
LINE BROADENING
MICROSTRUCTURE
OXIDATION
OXIDES
OXYGEN COMPOUNDS
POWDERS
RAMAN SPECTRA
SPECTRA
TITANIUM COMPOUNDS
TITANIUM OXIDES
TRANSITION ELEMENT COMPOUNDS
VAPOR CONDENSATION
VERY HIGH TEMPERATURE