High-temperature X-ray diffraction and specific heat studies on GdAlO{sub 3}, Gd{sub 3}Al{sub 5}O{sub 12} and Gd{sub 4}Al{sub 2}O{sub 9}

Journal Article · Wed Aug 15 00:00:00 EDT 2007 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2007.06.003· OSTI ID:21043820

Chaudhury, Satyajeet ^[1]; Parida, S C ^[2]; Pillai, K T; Singh Mudher, K D ^[1]

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1. Fuel Chemistry Division, RC and I Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)
2. Product Development Section, RC and I Group, Bhabha Atomic Research Centre, Trombay, Mumbai 400085 (India)

Gadolinium aluminates, GdAlO{sub 3}, Gd{sub 3}Al{sub 5}O{sub 12} and Gd{sub 4}Al{sub 2}O{sub 9} were synthesized by the solution combustion method. Very fine particles in the nanoparticle range of {approx}10-20 nm could be prepared by this method as evidenced by surface area measurement by multipoint BET method. Thermal studies on these compounds were carried out using high-temperature X-ray diffraction (HT-XRD) and differential scanning calorimetry (DSC) methods. The thermal expansion coefficients of GdAlO{sub 3}, Gd{sub 3}Al{sub 5}O{sub 12} and Gd{sub 4}Al{sub 2}O{sub 9} were calculated from the lattice parameter data and specific heats were calculated from DSC data. The lattice parameters of GdAlO{sub 3} and Gd{sub 3}Al{sub 5}O{sub 12} were found to increase linearly with temperature whereas Gd{sub 4}Al{sub 2}O{sub 9} did not show a linear trend. The specific heats of these compounds show an increasing trend with increase in aluminum atom fraction. Based on the thermodynamic data available in the literature and the specific heat data obtained in this study, oxygen potential diagram was constructed at 1000 K. - Graphical abstract: Isothermal oxygen potential diagram for the system Gd-Al-O at 1000 K.

• OSTI ID: 21043820
• Journal Information: Journal of Solid State Chemistry, Vol. 180, Issue 8; Other Information: DOI: 10.1016/j.jssc.2007.06.003; PII: S0022-4596(07)00226-5; Copyright (c) 2007 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved; Country of input: International Atomic Energy Agency (IAEA); ISSN 0022-4596
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
ALUMINATES
CALORIMETRY
COMBUSTION
GADOLINIUM COMPOUNDS
LATTICE PARAMETERS
OXYGEN POTENTIAL
SPECIFIC HEAT
TEMPERATURE RANGE 0400-1000 K
THERMAL EXPANSION
X-RAY DIFFRACTION