Synthesis of Complex Perovskite Oxides via Nanosheets Process

Complex perovskite oxides of Sr0.5(Nb0.5Ta0.5)O3 were synthesized by reassembling (SrNb2O7)2− and (Sr1.5Ta3O10)2− nanosheets followed by topochemical dehydration with heat treatment. Atomic force microscopy (AFM) images showed that the thicknesses of the (SrNb2O7)2− and (Sr1.5Ta3O10)2− nanosheets were approximately 6 nm (7 unit layers) and 4 nm (3 unit layers), respectively. Raman scattering measurement has suggested that nanosheet-processed Sr0.5(Nb0.5Ta0.5)O3 with B-site-cation ordering has a superlattice-like structure composed of alternating layers of Sr0.5NbO3 and Sr0.5TaO3 along the c-axis. Nanosheet-processed Sr0.5(Nb0.5Ta0.5)O3 with B-site-cation ordering exhibited a dielectric permittivity of 42 (1 MHz), which was lower than that of solid-state-reacted samples (65) with disordered B-site cations.