Controllable synthesis and morphology-dependent photoluminescence properties of well-defined one-dimensional Zn2GeO4:Mn2+ nanostructures

A variety of uniform and well-dispersed one-dimensional Zn 2 GeO 4 :Mn 2+ phosphors have been synthesized via a facile solvothermal process with H 2 O/EG as solvent. During the synthesis process, the component of solvent and the addition of PEG surfactant play an important role in determining the structure, particle size, and morphology of the final product. Under ultraviolet light excitation, the pure Zn 2 GeO 4 sample shows bluish-white emission which is attributed to the native defects present in the Zn 2 GeO 4 host. When Zn 2+ ions are partially substituted by Mn 2+ , the as-synthesized Zn 2 GeO 4 :Mn 2+ samples exhibit intense green emission that corresponds to the d-d transition ( 4 T 1 → 6 A 1 ) of Mn 2+ ions. The luminescence mechanisms of the Zn 2 GeO 4 :Mn 2+ samples were investigated in detail by using the CASTEP code based on density functional theory (DFT). It is expected that the as-synthesized Zn 2 GeO 4 :Mn 2+ phosphors can be potentially applied in lighting, optical displays, and optoelectronic devices .