Hydrothermal synthesis, characterisation and influencing factors of Zn2GeO4 hexagonal prism

Monodisperse Zn₂GeO₄ hexagonal prisms with about 6 m in length have been successfully prepared via a facile hydrothermal synthesis approach, employing zinc acetate and germanium dioxide as starting materials, trisodium citrate as coordination reagent. The phase and morphology of the product were characterised by powder X-ray diffraction, energy dispersive spectrometry, X-ray photoelectron spectrum and scanning electron microscopy. Some influencing factors such as the reaction time, temperature, the volume of glycerol and the amount of trisodium citrate were revealed to play crucial roles in the formation of Zn₂GeO₄ hexagonal prisms. A possible growth mechanism is proposed based on the experimental results. In addition, the UV-vis diffuse reflectance spectrum of the as-prepared Zn₂GeO₄ sample gave the value of optical absorption edge energy to be 4.54 eV.