GeO2 nanotubes and nanorods synthesized by vapor phase reactions

Bulk-quantity GeO2 nanorods and nanotubes have been synthesized by simple thermal evaporation of metallic germanium powders. The nanorods and nanotubes have a diameter of about 100-150 nm and length of about 1 μm. Many of the nanotubes have a serrated out surface which is formed by twin crystals. The twin boundary can strengthen the mechanical property and increase the electrical resistance and thus vary the physical property of GeO2. The products can emit bright blue light with a peak at 448 nm under excitation at 381 nm at room temperature. So the products may have potential application in future integrated optical devices.