Nanofiber coated structures

It has been known since the early stage of conducting polymer research that polyandine fibrils of 100 nm in diameter can naturally form on the surface of an electrode [4,40-45] with a compact microspheriod underlayer. Some recent work demonstrates that pure polyaniline nanofibers can be obtained without the need for any template by controlling the polymerization rate [46—48]. Although this process is not readily scalable from a materials point of view, such work could be very important for making functional devices, since nanofiber-coated electrodes can be used as a platform to fabricate sensors and transistors. Interconnected network-like structures with polyaniline nanoKnkers 10-50 nm wide have also been identified in polymer blends [49-51]. 

Various strategies are used to produce electrode structures within the membrane pores, including sol—gel synthesis, CVD, eiectrodeposition, and electroless deposition. With careful control of the synthetic conditions, the pores are either filled completely or preferentially coated at the pore walls, producing hollow tubes (see Figure 10b). Following infiltration with the desired electrode material, the membrane is subsequently removed under conditions that do not disturb the active material, leaving an array of either solid nanofibers or nanotubes attached to a current collector like the bristles of a brush (Figure 11). In this case there is very limited interconnectedness between the nanofibers, except at the current collector base. 

Reference experiments show that non-coated [Pt(NH3)4](HC03)2 nanofibers are not stable over long periods. They tend to agglomerate to non-regular structures. Only the rigid Si02 layers, forming the silica walls, stabilize the needle-like structure. 

Fig. 3 (a, b) SEM micrographs of HUVEC cells on fibronectin-coated staich/PCL scaffolds, showing the nano/microfiber combined scaffold after 3 days of culture. Note the ability of the ECs to use the nanofibers to span across the microfiber structure (Adapted from [54])... 

Fig. 59 a SEM image of a glass/ZnO nucleation layer/ZnO nanocarpet structure. The ZnO nanofibers are grown from an aqueous solution of zinc nitrate, and the nucleation layer is spin-coated from a zinc acetate solution, b SEM image of P3HT intercalated into the nanocarpet structure. (Reprinted from [280], 2006, with permission from Elsevier)... 

Structured supported ionic liquid-phase (SSILP) catalysis is a new concept that combines the advantages of ionic liquids (ILs) as solvents for homogeneous catalysts with the benefits of structured solid catalysts. In an attempt to prepare a homogeneous IL film on a microstructured support, SMFs were coated by a layer of carbon nanofibers as described above. An IL thin film was then immobilized on the CNF/SMF support. The high interfacial area of the IL film enabled the efficient use of a transition metal catalyst for the selective gas-phase hydrogenation of acetylenic compounds [267,268]. 

PANI-Coated Core/Shell-Structured Nanofibers... 

Araujo et al. (2008) prepared PCL electrospun nanofiber meshes coated with a biomimetic calcium phosphate (BCP) layer that mimics the extracellular microenvironment found in the human bone structure. The deposition of a calcium phosphate layer, similar to the inorganic phase of bone, on the PCL nanofiber meshes was... 

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