Solution-based fabrication of perovskite nanosheet films and their dielectric properties

We report a solution-based approach for fabricating perovskite nanofilms using a La_0:95Nb₂O₇ perovskite nanosheet, a two-dimensional nanomaterial prepared by delaminating layered perovskite KLa_0:95Nb₂O₇ into single-molecule-thick sheets. A layer-by-layer approach using Langmuir-Blodgett deposition was effective for fabricating uniform and highly dense nanofilms of perovskite nanosheets on an atomically flat SrRuO₃ substrate. Structural analysis using X-ray diffraction, transmission electron microscopy, and hard X-ray photoelectron spectroscopy revealed that these films are composed of a well-ordered lamellar structure without an interfacial dead layer. The nanofilms showed stable dielectric response with ε_r ≃ 45 for thickness even down to 6nm.