Preparation and photoluminescence properties of amorphous silica nanowires

Bulk-quantity amorphous silica nanowires (SiONWs) have been synthesized by carbothermal reduction reaction between silicon dioxide and active carbons. Transmission electron microscopy (TEM) image shows the formation of the nanowires at a diameter of 60–110 nm and a length up to hundreds micrometers. Besides most smooth-surface polyp-shaped nanowires, two other forms of nanowires, named amoeba-shaped and frog-egg-shaped nanowires, have also been observed. The nanowires can emit stable and high brightness blue light at 435 nm (2.85 eV) under excitation at 260 nm (4.77 eV). The formation of the nanowires into different shapes may be explained by the vapor–liquid–solid (VLS) mechanism.