Phase-controllable synthesis, shape evolution and optical performances of CePO4 nanocrystals via a simple oil-bath route

Abstract

Rare-earth inorganic orthophosphates have been attracting considerable research interest because of their significant luminescent properties. In the present work, we employed a facile oil-bath route to successfully realize phase-controlled synthesis of CePO₄ nanocrystals. The reactions were carried out at 110 °C for 30 min. The phases of the as-obtained products were determined by X-ray powder diffraction (XRD) analyses. Experiments showed that a mixed phase of hexagonal and monoclinic CePO₄ was prepared at the EG/H₂O volume ratio of 14/5, keeping the introduced EG/H₂O total volume of 19 mL unchanged. Hexagonal CePO₄ nanocrystals were obtained at the EG/H₂O volume ratio below 14/5; while at a volume ratio above 14/5, monoclinic ones were produced. Interestingly, the morphology of the final product underwent a change from long nanorods, to short nanorods, to nanorod bundles, to shuttle-like nanocrystals, and finally to spheroid nanocrystals with the increase of the EG/H₂O volume ratio. Furthermore, the optical performances of the final products with different forms were also investigated.