  As candidate tritium breeder materials for use in the ITER helium cooled
pebble bed, ceramic multiphasic compounds lying in the region of the
quasi-binary lithium metatitanate- lithium orthosilicate system may exhibit
mechanical and physical advantages relative to single phase materials. Here we
present an organometallic solution-based synthesis procedure for the
low-temperature fabrication of compounds in the Li2TiO3 - Li4SiO4 region and
investigate phase stability and transformations through temperature varied
X-ray diffraction and scanning calorimetry. Results demonstrate that the
metatitanate and metasilicate phases Li2TiO3 and Li2SiO3 readily crystallise in
nanocrystalline form at temperatures below 180{\deg}C. Lithium deficiency in
the region of 5% results from Li sublimation from Li4SiO4 and/or from excess Li
incorporation in the metatitanate phase and brings about a stoichiometry shift
and product compounds with mixed lithium orthosilicate/ metasilicate content
towards the Si rich region and predominantly Li2TiO3 content towards the Ti
rich region. Above 1150{\deg}C the transformation of monoclinic to cubic
{\gamma}-Li2TiO3 disordered solid-solution occurs while the melting of silicate
phases indicates a likely monotectic type system with a solidus line in the
region 1050{\deg}-1100{\deg}C. Synthesis procedures involving a lithium
chloride precursor are not likely to be a viable option for breeder pebble
synthesis as this route was found to yield materials with a more significant
Li-deficiency exhibiting the crystallisation of the Li2TiSiO5 phase at
intermediate compositions.
