Preparation, Characterization, and Ferroelectric Properties of the Alkylamine-Intercalated Layered Perovskite-Type Oxides (CnH2n+1NH3−Sr2Nb3O10, n = 1−6)

A series of alkylamine-intercalated layered perovskite-type oxides, C n H 2 n +1 NH 3 −Sr 2 Nb 3 O 10 ( n = 1−6), were prepared through a stepwise exchange process. X-ray powder diffraction (XRD) patterns of the samples showed a gradual increase of the interlayer spacing from 4.3 to 18.0 Å and the formation of monolayer and bilayer structures of alkyl chains between the perovskite layers. Infrared spectra (IR) and Raman spectra of the samples revealed the strong impact of the intercalated ions on the lattice of the perovskite layer. Ferroelectric hysteresis loops were observed in these oxides. In particular, the fatigue property was measured on the sample CH 3 (CH 2 ) 4 NH 3 −Sr 2 Nb 3 O 10 (donated as ASNO5). It did not show fatigue after 10 11 switching circles. This series of oxides may make up a new group of materials with good fatigue-free ferroelectricity. Furthermore, controllability of the interlayer height provides a useful mechanism for studying the interaction (e.g., ferroelectric coupling) between the ferroelectric layers.