Synthesis, Stability, and Crystal Chemistry of Dibarium Pentatitanate

摘要: Only ZrO2 was found to stabilize the phase previously reported as “Ba2Ti5O12.” A metastable corresponding this compound form between 650° and 675°C from hydrolyzed ethoxide precursors. The stability increased ∼850°C by addition of 1 2 mol% Nb2O5 precursor solutions. Addition 5 SnO2 failed yield appreciable amounts in solid-state preparations, contrary previous report. 8 ZrO2, however, did produce desired reported, both with without additional Nb2O5, apparently stable >1300°C. Small single crystals, picked a ZrO2-stabilized specimen showed Ba2Ti5-xZrxO12 be 10-layer structure, triclinic, pseudo-orthorhombic A-centered symmetry =9.941(5), b= 11.482(4), c= 23.528 (10) × 10–1 nm. reduced triclinic unit cell has = 9.941, 11.482, 13.090 nm, α= 116.01°, β= 90.0°, γ= 90.0°.