Hydrothermal synthesis of NaxFexTi2-xO4 from natural ilmenite sand: A CaFe2O4 structure type compound
Abstract
NaxFexTi2-xO4 a compound from the CaFe2O4 structure type group, was obtained via hydrothermal route at a temperature lower than 200 {ring operator}C for the first time. Natural ilmenite sand, a low cost reagent, was used as a precursor and reacted with 10 mol/l NaOH for 70 h to obtained high yield (92% wt) of NaxFexTi2-xO4 with x ∼ 0.76 - 0.79, as evaluated through the Rietveld refinement and quantitative phase analysis of X-ray powder diffraction data. Transmission Electron Microscopy showed that NaxFexTi2-xO4 appears in submicron to micron crystals with well-defined facets, growing along the [001] crystallographic direction, which means that the tunnels, a peculiarity of this crystal structure, are oriented along the direction of growth. © 2007 Elsevier Ltd. All rights reserved.
Keywords:
CaFe2O4 structure type / hydrothermal synthesis / scanning electron microscopy / X-ray scattering / transmission electron microscopySource:
Solid State Communications, 2008, 145, 7-8, 346-350Publisher:
- Elsevier
Projects:
- Brazilian National Council for the Scientific and Technological Development (CNPq)
- Ministry of Science and Environmental Protection of Serbia (post-doctoral scholarship)
DOI: 10.1016/j.ssc.2007.12.006
ISSN: 0038-1098