Back to Search
Start Over
Crystal structure, optical properties and colouring performance of karrooite MgTi2O5 ceramic pigments
- Source :
-
Journal of Solid State Chemistry . Nov2007, Vol. 180 Issue 11, p3196-3210. 15p. - Publication Year :
- 2007
-
Abstract
- Abstract: Karrooite, MgTi2O5, is a promising ceramic pigment due to its high refractoriness and refractive indices, as well as its ability to host transition metal ions in two crystallographically distinct octahedral sites. The colouring performance was investigated combining X-ray powder diffraction with UV–vis–NIR spectroscopy on karrooite doped with V, Cr, Mn, Fe, Co or Ni (M) according to the formula Mg1− x Ti2− xM 2 x O5, with x=0.02 and 0.05. Transition metals solubility in the karrooite lattice is not complete and a second phase is always present (geikielite or rutile). Structural data proved that incorporation of different chromophore ions into the karrooite structure affects unit cell parameters, bond length distances and angles, site occupancies and therefore cation order–disorder. Optical spectra exhibit broad absorbance bands of Co(II), Cr(IV), Fe(III), Mn(II), Mn(III), Ni(II), V(IV) with distinct contributions by cations in the M 1 and M 2 sites. Karrooite pigments have colours ranging from orange to brown-tan (Cr, Fe, Mn, V) to green (Co) and yellow (Ni) that are stable in low-temperature (<1050°C) ceramic glazes and glassy coatings. [Copyright &y& Elsevier]
- Subjects :
- *SPECTRUM analysis
*IONS
*TRANSITION metals
*ELECTRONS
Subjects
Details
- Language :
- English
- ISSN :
- 00224596
- Volume :
- 180
- Issue :
- 11
- Database :
- Academic Search Index
- Journal :
- Journal of Solid State Chemistry
- Publication Type :
- Academic Journal
- Accession number :
- 27692220
- Full Text :
- https://doi.org/10.1016/j.jssc.2007.08.029