花球状YBO_3∶Eu^(3+)的水热合成与表征

Hydrothermal Synthesis and Characterization of Flowerlike YBO_3∶Eu^(3+)

采用水热法制备了均匀分散、具有花球形貌的YBO3:Eu3+.利用X射线衍射仪、X射线能量仪、高分辨透射电镜、扫描电镜等手段对其结构、形貌进行了研究,发现其为六方球霰石晶相,仅含有Y、O、B、Eu元素,微球直径约1～2μm,组装成花球的薄片厚度约100nm.提出了其形成机理:在水热过程中生成的YBO3晶核在六亚甲基四胺(HMT)的调节下各向异性生长为二维薄片,并最终组装成为花球状结构.研究发现得到的YBO3:Eu3+在612nm表现出显著的红光发射,并且由于Eu3+附近晶体场对称性降低,样品表现出较高的红光/橙光(R/O)比率.

YBO3∶Eu3＋ microspheres with flower-like structures were fabricated by a facile hydrothermal method. The composition, structure and morphology of obtained YBO3∶Eu3＋ were studied by means of XRD、EDX, HRTEM and SEM. The as-prepared YBO3∶Eu3＋ microspheres show hexagonal vaterite phase with the elements of Y, O, B, Eu to be found. The YBO3 microspheres, with an average diameter of 1-2μm, are composed of nanosheets with thickness of 100nm. The formation mechanism of the flower-like structures is also proposed. The YBO3∶Eu3＋ samples have a strong red emission at 612nm and a high R/O ratio under ultraviolet excitation, which indicate lower symmetry of crystal field around Eu3＋ in such flower-like structures.