Stable high-field anodization (1500–4000 A m−2) for the fabrication of highly ordered porous anodic alumina films has been realized in a H3PO4–H2O–C2H5OH system. By maintaining the self-ordering voltage and adjusting the anodizing current density, high-quality self-ordered alumina films with a controllable inter-pore distance over a large range are achieved. The high anodizing current densities lead to high-speed film growth (4–10 µm min−1). The inter-pore distance is not solely dependent on the anodizing voltage, but is also influenced by the anodizing current density. This approach is simple and cost-effective, and is of great value for applications in diverse areas of nanotechnology.

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Highly ordered TiO(2) nanotubular arrays have been prepared by two-step anodization under high field. The high anodizing current densities lead to a high-speed film growth (0.40-1.00 microm min(-1)), which is nearly 16 times faster than traditional fabrication of TiO(2) at low field. It was found that an annealing process of Ti foil is an effective approach to get a monodisperse and double-pass TiO(2) nanotubular layer with a gradient pore diameter and ultrathin tube wall (nearly 10 nm). A higher anodic voltage and longer anodization time are beneficial to the formation of ultrathin tube walls. This approach is simple and cost-effective in fabricating high-quality ordered TiO(2) nanotubular arrays for practical applications.

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A two-step high field anodization and a controllable barrier layer removing process have been used for the fabrication of porous anodic alumina (PAA) with different morphologies. Based on the PAAs, porous noble metal films with widely tunable pore size and inter-pore distance have been realized by a simple sputtering method. Their morphology and optical properties were studied with a field-emission scanning electron microscope, and ultraviolet and ultraviolet-visible spectrophotometers. An enhanced light transmission of the nanoporous metal films was detected. The transmissivity of a normal incidence light can be enhanced over ten times within a certain selected wavelength range. The intensity and position of the transmission peak depend on the morphology and porosity of the metal films.