The template synthesis method based on deposition of materials inside well-defined
uniform pores of isoporous membranes offers unique possibilities of manufacturing one-dimensional, high aspect ratio cylindrical species with lateral dimension below 100 nm, practically from any solid material (carbon, metals, metal oxides, polymers) in the form of rods, wires, tubules, multiwall tubules and multilayer rods. Growing interest in template-based synthesis is the result of search for novel methods of manufacturing materials with predefined shapes and dimensions in nanorange, preferentially based on assembling them directly from molecules.
Two types of available commercially templates are commonly used for nanomaterials synthesis - Track-etched polymeric Membranes (TM) and Anodic Alumina Oxide (AAO) membranes. Due to the method of preparation of TM (irradiation of thin polymer films by heavy ion beam following by the chemical etching) the distribution of pores over film area is stochastic. The pore diameters depend on chemical etching conditions; the smallest available diameters are usually of about 50 nm. In contrast AAO membranes obtained by anodic oxidation of aluminium foil in appropriate solution, are characterised by highly ordered, closely packed array of columnar, nearly hexagonal cells. The porosity of these membranes is about 66 %. The diameter of pores can be varied in the range 100-500 nm.
The kinetics of deposition process into pores of nanoporous membrane is still not well-understood. In many experiments on deposition into the pores, an observation has been made that chemical properties of pore walls (chemical groups present on the surface) play an important role in kinetics of the deposition process, in particular, during its initial step. In the present paper the kinetics of deposition of conducting polypyrrole polymer inside TMs is described.
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