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.

Europium-doped lutetium (Lu2O3:Eu3+ ) powders were prepared by micro-emulsion method. A small amount of an aqueous solution of Lu(NO3)3, Eu(NO3)3 and aqueous ammonia was slowly dropped into the water-in-oil micro-emulsion system (water / cetyl trimethyl ammonium bromide (CTAB) / n-butyl alcohol and cyclohexane) under vigorous stirring at 80 °C. The precipitates were obtained by Ostwald’s ripening at 250 °C for 6 h, which were then heated at 400 °C, 600 °C and 800 °C. The SEM morphology showed that the powders were rods of about few hundred nanometers in length and 40 nm in diameter. The spectrograms of X-ray diffraction (XRD) demonstrated that the Lu2O3:Eu3+ crystallinity was enhanced with the increasing of temperature. The photoluminescence results revealed that the intense emission bands centered at 612 nm. This method provides a new way to obtain different morphology and luminescent properties of Lu2O3:Eu3+ powder.