Sol-gel synthesis of Ln₂(Ln = La, Nd)Ti₂O₇

Lanthanum and neodymium titanates were prepared by a sol-gel route. Synthesis of La₂Ti₂O₇from pure alkoxide precursors yielded an intermediate perovskite type phase, La_(1–x)TiO₃, which partially transformed to La₂Ti₂O₇on heating to 1500 °C. Substitution of the lanthanum acetylacetonate for alkoxide precursor yielded La₂Ti₂O₇without any intermediate phase at a very low temperature of 700 °C. Sintering of the La₂Ti₂O₇gel powder yielded a highly dense ceramic with ∼97% theoretical density. Similar sintering treatment resulted in ∼92% theoretical density for Nd₂Ti₂O₇.