Fabrication of Li2TiO3 spherical microparticles from TiCl4 by a classical, inorganic sol-gel route; characteristics and tritium release properties

Medium sized spherical particles of Li₂TiO₃ (with diameters below 100 m) can be fabricated by a classical, inorganic sol-gel process, from commercially available TiCl₄. Elaborated process consists of the following main steps: (1) dissolving of TiCl₄ in concentrated aqueous HCl; (2) formation of sol emulsion in 2-ethylhexanol-1 containing the surfactant SPAN-80 (EH); (3) gelation of emulsion drops by extraction of water with partially dehydrated EH; (4) impregnation of gel to Li : Ti molar ratio (MR) = 2; (5) thermal treatment at 1200°C. This temperature can be significantly lowered (to 750°C) by chemical treatment of chloride precursors (gels or starting solution TiCl₄) with aq. ammonia or better with nitric acid. Tritium release from sol-gel made Li₂TiO₃ micro-spheres were found very close to that observed for other traditional materials, however for the first sample process starts slightly earlier.