| Recently, anodic aluminum oxide (AAO) membranes with a regular porous structure have been prepared by electrochemical methods and have widely been used to produce various nanostructured materials within highly ordered channels in the AAO membrane in which the diameters and lengths of the inserted nanowire can be well controlled. In this dissertation, after reviewing the latest development in research of the novel system of nano-array composite by using template method, reports my research work of fabricating metal/AAO nano-array composite and their novel optical properties in the past few years. Different metal/AAO composites ranging in volume fraction of the metal showed unusual size-dependent optical properties, some important results obtained are as following:1. Porous AAO are prepared by anodization of Al sheets in sulfuric, phosphoric and oxalic acid aqueous solutions. We have optimized the set of parameters, which make pore arrays in AAO membrane highly ordered. Changing the conditions of oxidizing, we obtained series of pore arrays with controlled structures, such as diameter (from 10 to 200 nm), depth (from 500 nm to 100 nm), and density (from 108 to 1011 cm-2).2. Series of aligned metal nano-arrays with controlled diameters, length, volume fractions and density are obtained by electrodepositing the metal in the corresponding AAO membranes which have the same structure parameters, or adopting different depositing conditions, such as voltage, time and pH.3. Ordered Co nano-arrays have been prepared via electrodeposition of the metal within the nanoporous AAO template. Measurements show that the optical properties of the Co/AAO composites depend on the length and the diameters of Co nano-wires. As the Co composition increased, the absorption band-edge is strongly red-shifted (115 nm) and the even reflectance of the composite change from 70 % to 6 %. Meanwhile the reflectance is more sensitive to the change of the diameter of Co nano-wire.4. We have fabricated Co/AAO and Ni/AAO nano-array composites in same conditions, and studied the optical properties of the two composite. The results show that the differences between the two composites are very large. Although the micrograph of the Ni nano-wire andthe Co nano-wire are nearly the same, as the metal composition increased, the absorption band-edge of the Ni/AAO composite is small red-shifted (13 run), however, the absorption band-edge of the Co/AAO composite is strongly red-shifted (80 nm). Meanwhile, the Ni/AAO and Co/AAO composite exhibit the optical features of the semiconductor with indirect and direct band gap respectively.5. Studied the plasma resonance absorption properties of the Ag/AAO nano-array composite. The spectral analysis shows that the surface plasmon resonance peak of Ag occurs at X =352 ~ 377 nm. As the Ag composition decreased, the dipolar plasma resonance absorption peak shifted to a longer wavelength, strengthened and gradually expanded. AAO membranes have small effect to the location of the absorption peak. The theoretical analysis shows the M-G calculated results are agreed well with the experimental ones.6. We have investigated the effect of Cu composition on the absorption properties of Cu/AAO nano-array composite in the wavelength range 200-1000 nm. The absorption characteristics was that the surface plasma absorption peak appeared around 570 nm shifted to a short wavelength and strengthened as the Cu composition increased. But the maximal shift range of the absorption-edge preponderated over 500 nm, and leaded that the dipolar plasma resonance absorption peak were covered up and gradually disappeared in the absorption spectrum. We theoretically explained the mechanism of the modulating action.
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