Controllable synthesis and tunable luminescence of yttrium orthoborate microcrystals with multiform morphologies and dimensions

Abstract

Uniform and well-dispersed YBO3 microcrystals with a variety of morphologies (cuboids, cubes, flat quadrilateral particles, etc.) have been synthesized via an easy-to-operate two-step method. During the synthesis process, the well-defined Y(B(OH)4)CO3 precursors with diverse shapes were fabricated by a facile wet-chemical method at ambient pressure, without any template, substrate, or catalyst. Finally, the YBO3 microcrystals which inherit the morphology and dispersity were obtained after a calcination process. The morphology and particle size of the Y(B(OH)4)CO3 and YBO3 microcrystals can be tuned in a controlled manner by simply changing the auxiliary solvent or reaction temperature and time. Upon UV or NIR excitation, the as-synthesized lanthanide ions (Eu3+, Tb3+, Eu3+/Tb3+, Yb3+/Er3+) doped YBO3 samples exhibit the intense characteristic down-conversion or up-conversion multicolor emissions. The dependence of luminescence intensity on different morphologies and crystallinity has also been studied. This facile synthesis strategy may be of significance for the design and preparation of other lanthanide orthoborates functional materials with well-defined morphologies.