Synthesis of ferroelectric KNbO3 nanosheets by liquid exfoliation of layered perovskite K2NbO3F

Ferroelectric perovskite KNbO3 (KNO) nanosheets with cubic and orthorhombic phases were synthesized by a simple soft chemistry exfoliation at room temperature. KNO nanosheets could be simply obtained by peeling off the layered precursor K2NbO3F in water, while the phase structure of KNO could be controlled by using different precursors. The cubic KNO nanosheets were formed by exfoliating-restacking, while the orthorhombic nanosheets were produced by nucleation-ripening. The photocatalytic performance of these nanosheets has been exploited in degradation Rhodamine B dye. The cubic KNO nanosheets showed obviously better photocatalytic activity, which could be ascribed to its highest symmetry in the bulk structure and its unique electron structure. The high activity of the ferroelectric two dimensional nanosheets indicates a broad spectrum of applications in the photocatalyst fields.