Preparation Of Anodic Aluminum Oxide Film And The Film Hole Electrodeposition Of Nickel

This essay reviews the methods for the fabrication of ordered nanostructure , especially the application of AAO template in producing ordered nanostructure. We have made AAO template under invariable potential, using sulfuric acid, oxalic acid , phosphate acid as electrolyte respectively .We have deposited nickel in both AAO template anodized in sulfuric acid and anodized in oxalic acid by way of pulse current and alternative current respectively , with Ni2SO4 and H3BO4 as electrolyte. We have analyzed the effects of heat treatment and deposition conditions on the morphology and the crystal structure of AAO template and AAO template with nickel deposited in its hole. We have also analyzed absorbability of visible and ultraviolet spectrum of AAO template with nickel deposited in its hole. We have used XRD to check the phase structure of anodized membrane and used SEM and TEM to investigate the morphology of anodized membrane, using the visible and ultra-violet spectrum to measure the light absorbability of anodized sulfuric membrane deposited with Ni.These results are deduced from our experiments: phase transformation from amorphous to -Al2O3 occurs after heat treatment at 930癈 ; the hole diameter of the membrane anodized in phosphate acid is approximately 50~70nm without ideal periodicity; the hole diameter of the oxalic acid membrane is approximately 40nm and the distance between the central points approximately 105nm with its hole axis parallel to each other . The distribution of hole on the plane ,which is vertical to the axis of the hole, is quasi-hexagon. The hole diameter of the sulfuric acid membrane is approximately 10nm with its hole axis parallel to each other. Both for anodized sulfuric acid membrane and anodized phosphate acid membrane without heat treatment, their morphologies of XRD spectrum are similar to the XRD spectrum of single crystal. However, after the crushing of the membrane the corresponding peak disappear. We draw the conclusion that the peak, similar to single crystal XRD spectrum ,is not caused by its crystal structure and that it might have something relating with the piled meso-structure occurred during the growth of the membrane. After the heat treatment, the phase structure of membrane anodized in sulfuric acid is -Al2O3 phase structure indicating its poor crystallinity and thermostablity both for membrane anodized in sulfuric acid and for membrane in anodized oxalic acid.while it is easy to deposit Ni into membrane anodized in sulfuric acid using AD, it is difficult in depositing Ni and Ag into membrane anodized in oxalic acid. The deposited Ni is amorphous, after annealing at 900 C, the structure of nickel transformed into fcc structure either with poor crystallinity or with nanometer grain, the absorbability of visible and ultra-violet spectrum of membrane with Ni deposited, anodized in sulfuric, is higher than membrane without Ni deposited, which is abnormal . the absorbability of membrane in anodized sulfuric with Ni deposited shows the abrupt decreasing between 300 nm-600nm.