Zn₂SiO₄:Eu³⁺ micro-structures: Controlled morphologies and luminescence properties

Zn₂SiO₄:Eu³⁺ phosphors with diverse morphologies, including rice-like, hexahedron-like, and column-like, have been successfully prepared by means of a simple hydrothermal approach followed by a subsequent calcinations process. The results indicate that the morphologies of the products can be adjusted by altering the pH value of the reaction system. The formation mechanisms of different morphologies of samples have been investigated in detail. Furthermore, under near ultraviolet excitation, the Zn₂SiO₄:Eu³⁺ exhibits strong red emission corresponding to the ⁵D₀→⁷F₂ transitions of the Eu³⁺ ions, which have potential applications in optical and biological areas. Meanwhile, luminescent characteristics of different morphologies have been explored and the column-like Zn₂SiO₄:Eu³⁺ sample presents an optimum red luminescence. The CIE chromaticity diagram and the symmetry of the different morphologies phosphors also have been explored. In addition, the concentration quenching effects and decay kinetics behaviors of Zn₂SiO₄:Eu³⁺ microstructures with optimum red luminescence were investigated and the strongest luminescent intensity and the longest lifetime were both in the composition of 0.03 mol Eu³⁺.