Structural and thermal properties of La-containing Dion – Jacobson homologous series

Structural and thermal properties of RbLaNan-2NbnO3n+1 (n ​= ​2, 3, 4) homologous series were studied. Crystal structures of RbLaNaNb3O10 and RbLaNa2Nb4O13 were refined using the Rietveld method. The thermal expansion behavior of compounds was established using high-temperature X-ray diffraction for all three phases. Chemical purity and stoichiometry of synthesized compounds were characterized by XRF spectroscopy. Differential thermal analysis (DTA) was used to explore the thermal stability of compounds. The optical band gap, valence band energy (EVB), and conduction band energy (ECB) were calculated from UV–vis spectroscopy data.