Nanotubes hard template preparation

Fig.18 PMMA/discotic composite nanofibers prepared inside AAO hard templates, a Nanotube (diameter about 400 nm) with a wall consisting of an outer PMMA layer and an inner (stained) discotic layer b nanorod (diameter 60 nm) with a disordered segmented morphology. Reproduced from [65]. (2005) Wiley-VCH...

Among the several fabrication methods, hard template method, which was pioneered by Martin et al., has been the most famous route of nanotubes and nanowires. Nanotubes of conducting polymers could be readily prepared by filling the nanopores with polymer or polymer solution using AAO template or track-etched PC membrane. PPV nanotube and nanorod had been fabricated in the pores of alumina or PC filters with pore diameter 10-200 nm by... 

Martin [21] proposed a mechanism for the growth of the nanostructures prepared by the hard-template method. However, the mechanism is insufficient in explaining the growth of partially filled nanotubes by an electrochemical template synthesis [36]. Recently, Lee and coworkers [37] investigated the electrochemical... 

Conductive polymeric nanostructures can be prepared by using hard or soft templates or with template-free methods. The template method has been extensively used because of its simplicity, versatility and controllability. Some further features on this topic are reported in Section 1.3. A typical hard template material can be a thin porous film of aluminum oxide or polycarbonate and polymeric materials ean be deposited into the pores to form nanotubes or nanowires. The electrochemical template method enables a better control of the dimensions compared with the chemical methods. In addition, the nanostructures produced by the electrochemical method are in solid contact with a base electrode that is beneficial for further processing steps when building an electrochemical device. 

In addition to spherical particle nanocomposites, the preparation of nanotubes and nanowires composites with both magnetic and electrical properties is of great interest due to the enhancement of the conductivity. In general, the room temperature conductivity increases when the diameter decreases [79]. Conducting polymer nanotubes can be chemically or electrochemically synthesized by hard and soft template or template-free method in the presence of magnetic nanoparticles [8, 23, 27]. 

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