Effect of added zinc on the properties of cobalt-containing ceramic pigments prepared from layered double hydroxides

Journal Article · Tue Sep 15 00:00:00 EDT 2009 · Journal of Solid State Chemistry

DOI:https://doi.org/10.1016/j.jssc.2009.07.011· OSTI ID:21370593

Perez-Bernal, M E; Ruano-Casero, R J ^[1]; Rives, V ^[1]

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1. GIR-QUESCAT, Departamento de Quimica Inorganica, Universidad de Salamanca, 37008 Salamanca (Spain)

Layered double hydroxides (LDHs) with the hydrotalcite-type structure containing Co and Al, or Zn, Co and Al in the brucite-like layers and carbonate in the interlayer have been prepared by coprecipitation. The Zn/Co molar ratio was kept to 1 in all samples, while the divalent/trivalent molar ratio was varied from 2/1 to 1/2. The samples have been characterised by element chemical analysis, powder X-ray diffraction, differential thermal and thermogravimetric analysis, temperature-programmed reduction and FT-IR spectroscopy. A single hydrotalcite-like phase is formed for samples with molar ratio 2/1, which crystallinity decreases as the Al content is increased, developing small amounts of diaspore and dawsonite and probably an additional amorphous phase. Calcination at 1200 deg. C in air led to formation of spinels; a small amount of NaAlO{sub 2} was observed in the Al-rich samples, which was removed by washing. The nature of the spinels formed (containing Co{sup II}, Co{sup III}, Al{sup III} and Zn{sup II}) strongly depends on the cations molar ratio in the starting materials and the calcination treatment, leading to a partial oxidation of Co{sup II} species to Co{sup III} ones. Colour properties (L*a*b*) of the original and calcined solids have been measured. While the original samples show a pink colour (lighter for the series containing Zn), the calcined Co,Al samples show a dark blue colour and the Zn,Co,Al ones a green colour. Changes due to the different molar ratios within a given calcined series are less evident than between samples with the same composition in different series. These calcined materials could be usable as ceramic pigments. - Abstract: Mixed oxides from layered double hydroxides (LDHs) with the hydrotalcite-type structure containing Co and Al or Zn, Co and Al in the brucite-like layers are potential candidates for ceramic pigments with tunable colour properties. Display Omitted

• OSTI ID: 21370593
• Journal Information: Journal of Solid State Chemistry, Journal Name: Journal of Solid State Chemistry Journal Issue: 9 Vol. 182; ISSN 0022-4596; ISSN JSSCBI
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ALUMINIUM COMPOUNDS
ALUMINIUM HYDROXIDES
ALUMINIUM OXIDES
AMORPHOUS STATE
CALCINATION
CERAMICS
CHALCOGENIDES
CHEMICAL ANALYSIS
CHEMICAL REACTIONS
COBALT COMPOUNDS
COBALT HYDROXIDES
COBALT OXIDES
COHERENT SCATTERING
COPRECIPITATION
DECOMPOSITION
DIFFRACTION
GRAVIMETRIC ANALYSIS
HYDROGEN COMPOUNDS
HYDROXIDES
INFRARED SPECTRA
MINERALS
OXIDE MINERALS
OXIDES
OXYGEN COMPOUNDS
PIGMENTS
PRECIPITATION
PYROLYSIS
QUANTITATIVE CHEMICAL ANALYSIS
SCATTERING
SEPARATION PROCESSES
SPECTRA
SPINELS
TEMPERATURE RANGE
TEMPERATURE RANGE 1000-4000 K
THERMAL ANALYSIS
THERMAL GRAVIMETRIC ANALYSIS
THERMOCHEMICAL PROCESSES
TRANSITION ELEMENT COMPOUNDS
X-RAY DIFFRACTION
ZINC COMPOUNDS
ZINC HYDROXIDES
ZINC OXIDES