Preparation and photoluminescence properties of crystalline GeO2 nanowires

Bulk-quantity GeO2 nanowires (GeONWs) have been synthesized by carbothermal reduction reaction between germanium dioxide and active carbons. Transmission electron microscopy (TEM) image shows the formation of the nanowires at a diameter about 50–120 nm and a length up to hundreds of micrometers. The nanowires can emit stable and high brightness blue light at 485 nm (2.56 eV) under excitation at 221 nm (5.61 eV). The intensity of the emission is one order of magnitude higher than that of GeO2 powders. The photoluminescence (PL) may originate from radiative recombination between an electron on VO× and a hole on (VGe,VO)× in the GeONWs. The nanowires may have potential applications in one-dimensional optoelectronic nanodevices.