Aligned Nanorods of AlPO4-5 Within the Pores of Anodic Alumina
Anodic aluminium oxide has been identified as a versatile porous template material having high pore density, (up to 1010 cm-2), controllable channel length and monodisperse pore diameter within the range 20-250 nm. A number of studies have demonstrated the concept of utilizing the porous structure for directing the growth of various nanostructures. An example of this is the growth of crystals of the aluminophosphate AlPO4-5 within the anodic nanochannels. The high aspect ratio of the template pores encourages growth of the crystals in the preferred c-axis orientation. We have produced membranes of this material and investigated the degree of crystal alignment using X-ray diffraction. The relative degree of preferred orientation is over 200 for a typical membrane. Field emission SEM micrographs clearly show the aligned crystals within the pores. The inclusion of luminescent guest molecules within the pores of the zeolite has also been achieved. This work describes the synthesis, characterization and potential application of these membranes.