Preparation and study of porous anodic alumina film

Nanometer-scale Al2O3 template with highly ordered and closely packed hexagonal pore structure were prepared by a two-step electrochemical anodizing process in H2SO4 and H2C2O4 respectively. The Al2O3 films with adjustable and controllable pore diameter were measured by SEM. The depth of the pores and the thickness of the films can be controlled by altering the anodic voltages, oxidizing time, temperature and concentration of electrolyte solutions. The remained Al base was removed by dissolving in saturated HgCl2 solution to get Al2O3 films with typical hexagonal structure. The optimum conditions of preparation were studied and discussed.