Synthesis and thermal stability studies of a series of metastable Dion-Jacobson double-layered neodymium-niobate perovskites

摘要

The Dion-Jacobson double-layered perovskite, RbNdNb_2O_7, is used as a precursor to synthesize the series ANdNb_2O_7 (A = H, Li, Na, K, NH_4,Ag),and (MC1)NdNb_2O_7 (M=Mn, Fe,Cu) through ion-exchange reactions ≤ 400 ℃. Thermal stability studies indicated that most of these compounds are metastable. A combination of X-ray powder diffraction and differential thermal analysis were used to determine various low temperature decomposition pathways;these pathways were very dependent on the interlayer species. Overall the ANdNb_2O_7 series was found to be less stable than the corresponding lanthanides, ALaNb_2O_7.