Uniform and high-quality submicrometer tubes of GaS layered crystals

GaS, group III-VI semiconductor compound, is known to possess a layered structure. In this letter, uniform and high-quality GaS submicrometer tubes have been synthesized via a simple high-temperature thermal reaction route. Each GaS tube is uniform in size, and has length up to tens of microns and outer diameter of similar to 200-900 nm; some of the tubes are partially filled with liquid metallic Ga rods. Photoluminescence spectrum reveals that the GaS tubes have two strong emission bands centered at similar to 585 and similar to 615 nm. Possible reaction processes and a rolling-up growth mechanism of as-grown GaS tubes were briefly discussed. (C) 2005 American Institute of Physics.