Large-scale synthesis and the roles of growth conditions on the formation of Zn2GeO4 nanorods

Large-scale Zn2GeO4 nanorods with a length of about 10 μm have been synthesized via a facile hydrothermal process in the absence of any surfactant. The synthesized nanorods are single crystals with a rhombohedral phase. The dependence on the growth conditions, such as reaction temperature, reaction time, compactness and GeO2 concentration, of the formation, morphologies and sizes of the Zn2GeO4 nanostructures has been investigated. Proper selection and combination of the growth conditions are the key aspects to control the formation, morphologies and sizes of the Zn2GeO4 nanostructures. The nucleation and crystalline growth mechanism are proposed to explain the formation and growth of Zn2GeO4 nanorods. The photoluminescence spectrum of the Zn2GeO4 nanorods exhibits three fluorescence emission peaks centered at 421, 488 and 529 nm when the excitation wavelength is 235 nm.