Preparation and Characterization of Alumina Nanofibers by Gas-Solid Reaction Method

Abstract

Using gas-solid reaction method, the non-crystalline alumina nanofibers with different morphology and aspect ratios could exuberantly grow by feeding air into one closed box or bubbling air into several organic liquids which contained the thin aluminum amalgam sheet at room temperature. Their diameters were about 2-10nm, whereas the length-diameter ratios were distributed widely. The diameters and length could be controlled by adjusting the kinds of the organic reagent. The as-grown nanofibers were then heat-treated at temperatures range from 300 to 1000°C. The results of X-ray diffraction and thermo-gravimetric analysis indicated the γ-Al2O3 nanofibers would be produced at 500°C and the α-Al2O3 particles could be obtained at about 1000°C. The electron micrographs suggested the nanofibers growth direction was randomly in the air or organic solutions, except for growing regular naonofibers in polyoxyalklene-400. The growth mechanics of alumina nanofibers were briefly discussed.