Alkaline earth aluminate with rare earth ion doping have attracted an increasing attention because of their excellent illuminant properties. As the fast development of nanoscience, it is valuable and necessary to investigate one dimensional (1D) nanostructures of these aluminate luminescence materials in order to understand the influence of nanolization of these materials on their illuminant properties, such as frequency change. In this dissertation, MAl2O4：Eu2+ (M=Ca, Sr) nanocones and nanorods were synthesized by heat evaporation method. Morphologies, microstructures and optical illuminance of these 1D nanomaterials were characterized using X-ray diffraction (XRD), scanning electron microscope (SEM), high-resolution transmission electron microscope (HRTEM), scanning transmission electron microscope (STEM), X-ray energy dispersive spectrum (EDS), photoluminescence spectrum (PL) and cathodeluminescence spectrum (CL).
The length of CaAl2O4：Eu2+ nanocones rangs from few microns to several ten microns, and their diameter is hundreds nanometer to several microns at one end and tapers off to a several ten to several hundred nanometers tip at the other end. The diameter of the nanorods ranges from several ten nanometers to several hundred nanometers, and their length is several to several ten microns. Both the nanocones and nanorods grow by the vapor-liquid-solid (VLS) mechanism along [010] direction and the normal direction of (100) and (001) face. A unknown wide emission band was identified at about 600nm in addition to the wide emission band peaking at about 440nm.
Typical SrAl2O4：Eu2+ nanocones and nanorods were also synthesized by two-step heat evaporation method. The products deposited in high temperature are mainly nanocones with zigzag edge and nanorods with the diameter ranging from several ten nanometers to few microns. In low temperature, however, only nanocones were synthesized with the same shape as CaAl2O4：Eu2+ nanocones. The length of the SrAl2O4：Eu2+ nanocones rangs from several microns to several ten microns, and their diameter is several hundred nanometers to several microns at one end and tapers off to a several ten to several hundred nanometers tip at the other end. The main growth direction is [010] and the normal direction of (100) and (001) face. The high yield of SrAl2O4：Eu2+ nanocones, which were synthesized by one-step heat evaporation method, deposited in a cluster, and have smaller size than the products prepared by two-step heat evaporation method. All of the SrAl2O4：Eu2+ nanocones and nanorods grow by the VLS mechanism and exhibit a small blue-shift of about 10nm, which may attribute to the quanta size effect.
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