Synthesis of aligned ripple-like and helical structure silica fibres

Highly aligned ripple-like silica fibres, as well as helical structure fibres have been synthesized by a chemical vapor deposition technique. The as-grown product was characterized by X-ray diffraction, scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy and selected-area electron diffraction. The results showed that the fibres were amorphous in nature with average diameters of 800 nm and lengths of several hundred micrometers. The formation of the fibres could be explained by the vapor–solid (VS) mechanism and the helical structure might be formed by a perturbation during the growth of the ripple-like fibres. The photoluminescence (PL) spectrum of the silica fibres showed two strong blue emission peaks at 450 nm (2.75 eV) and 415 nm (2.99 eV) under excitation at 260 nm.