Low-Temperature Chemical Synthesis and Microstructure Analysis of GeO2 Crystals with α-Quartz Structure

Germanium dioxide (GeO2) crystals were prepared by precipitation from water solution of ammonium germanate with nitric acid at a relatively low-temperature (100 degrees C). The grown GeO2 crystals were characterized to study their microstructure and chemical analysis using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), infrared (IR) spectroscopy, and Raman spectroscopy techniques. The results indicate that the grown GeO2 crystals exhibit a.-quartz type crystal structure. The lattice parameters obtained from XRD were a = 4.987(4) angstrom and c = 5.652(5) angstrom. The crystals formed were submicrometer in size and exhibited uniform shape and diameter, which is about 500 nm. The characterization using microscopic and spectroscopic measurements indicate a high structural quality of GeO2 crystals, in terms of control for morphology, single-phase, and chemical bonding and local structure, grown using the present approach.