Structural and optical properties of nanomaterials produced using template technique

In this thesis, we will report a unique method to produce mono-dispersed nanostructure arrays using nanoporous AlPO4-5 (AFI) single crystals as template. The task of this thesis is to characterize the structure of several nano-species formed in the channels of AFI crystals and investigate their physical properties. (I) Selenium nano species are fabricated in the channels of AFI single crystals by physical diffusion method. Highly ordered helical selenium chain arrays are evinced by X-ray scattering patterns. Raman spectra show that four possible types of Se clusters are formed, namely amorphous like selenium (a-Se), trigonal crystalline like selenium (t-Se), one dimensional selenium helix (Se chain), and selenium 8-member rings (Se8). (II) The highly-aligned mono-sized ultra small single-walled carbon nanotubes (SWNTs) are formed inside AFI matrix by pyrolysing tripropylamine (TPA) organic molecules in the channels. Transmission electron microscopy (TEM), diffuse x-ray diffraction, and micro-Raman measurements all consistently indicate that the diameter of SWNTs is ∼0.4 nm. (III) Styryl 7 dye molecules loaded AFI single crystals (dye/AFI) are also produced by physical diffusion method. The intensity of the polarized absorption and polarized photoluminescence (PL) bands of a single dye/AFI crystal is mainly proportional to cos2theta, where theta is the angle between the polarization direction and the c axis of the crystal, indicating that the dipole transition moment of the organic dye molecules is highly oriented in the channels. (Abstract shortened by UMI.)...