Synthesis of nanostructured palladium films on porous {alpha}-Al{sub 2}O{sub 3} substrates

The lamellar lyotropic liquid crystalline phases of Brij56 nonionic surfactants were used to template the deposition of nanostructured palladium films on {alpha}-Al{sub 2}O{sub 3} substrates. The reaction between hydrazine hydrate and Pd{sup 2+} dissolved within the aqueous domains of the liquid crystalline phase generated the nanostructured palladium. The X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission election microscopy (TEM) studies indicated that the resulting films possessed regular arrays of channels with periodicity of 1 nm, which was obviously smaller than that of the templates. The size mismatch might arise from the discharge of nitrogen during the reaction and the relatively low Pd{sup 2+} concentrations.