Porous aluminum oxide membranes with pore diameters smaller than 20nm were prepared by anodization of aluminum. Using these porous membranes as a template, we fabricated uniform gold cylinder arrays by electrodeposition of gold into the pores. All cylinders in the array were parallel, with their long axes perpendicular to the surface of the template. Electron microscopy, including transmission electron microscopy (TEM) and scanning electron microscopy (SEM), were employed to characterize the morphology of the templates and the fabricated nanometer scale of cylinder arrays. The extinction spectra of the arrays along the longer axes showed that the extinction maximal (λmax) shifted to a short wavelength and strengthened when the aspect ratio (l=d) of the cylinders increased. The dependence of the maximal (λmax) on the size was explained qualitatively by using the approximate dynamical Maxwell-Garnett model, and the calculated results were compared with the experimental ones.

The influence of bromine adsorption on copper electrodeposition on a polycrystalline gold electrode modified with self-assembled monolayers (SAMs) has been investigated by chronoamperometry and cyclic voltammetry. It was found that the deposition potential of copper was shifted negatively due to the SAMs. The hydrogen bond interaction between w-carboxyl thiols decreased the defect density of the SAMs and significantly retarded the deposition of copper. The presence of bromide anions also shifted the potential more negatively through adsorption into the defects of SAMs.

A new type of magnetic polymer microsphere containing acylhydrazine groups on the surface was synthesized. They can be reacted with formaldehyde to produce an electroactive adduct. Reduction of these derivatives following aggregation on a magnetic electrode is possible and is effective in the indirect determination of formaldehyde. The experimental conditions and electrode structure are discussed. Under the optimum conditions, it was found that the peak potential (Ep) of formaldehyde is 21.01V (vs. Ag/AgCl). Formaldehyde in the range 1-1000mg l21 can be determined. The detection limit for formaldehyde is 0.3mg l21 and the relative standard deviation for the determination of 100mg l21 formaldehyde was 2.26%. The method was applied to the determination of formaldehyde in environmental samples with satisfactory results.