Polypyrrole nanomaterials

Nanomaterials can also be applied to glucose biosensors to enhance the properties of the sensors and, therefore, can lead to smaller sensors with higher signal outputs. Carbon nanotubes have been incorporated in previously developed sensors and seen to increase the peak currents observed by threefold.89 Platinum nanoparticles and single-wall carbon nanotubes have been used in combination to increase sensitivity and stability of the sensor.90,91 CdS quantum dots have also been shown to improve electron transfer from glucose oxidase to the electrode.92,93 Yamato et al. dispersed palladium particles in a polypyrrole/sulfated poly(beta-hydro-xyethers) and obtained an electrode response at 400 mV, compared to 650 mV, at a conventional platinum electrode.94... 

The template-assisted synthetic strategies outlined above produce micro- or mesoporous stmetures in which amorphous or crystalline polymers can form around the organic template ligands (174). Another approach is the use of restricted spaces (eg, pores of membranes, cavities in zeolites, etc.) which direct the formation of functional nanomaterials within thek cavities, resulting in the production of ultrasmaU particles (or dots) and one-dimensional stmetures (or wkes) (178). For example, in the case of polypyrrole and poly(3-methylthiophene), a solution of monomer is separated from a ferric salt polymerization agent by a Nucleopore membrane (linear cylindrical pores with diameter as small as 30 nm) (179—181). Nascent polymer chains adsorb on the pore walls, yielding a thin polymer film which thickens with time to eventually yield a completely filled pore. De-encapsulation by dissolving the membrane in yields wkes wherein the polymer chains in the narrowest fibrils are preferentially oriented parallel to the cjlinder axes of the fibrils. 

Various kinds of conducting polymers can work as coimter electrode in DSSC. Poly(3,4-ethylenedioxythiophene) (PEDOT), polypyrrole (PPy), PANI are most investigated polymer materials. With the development of nanomaterial, the nanostructure has been introduced into previously mentioned polymers. These polymers are readily deposited by either chemical or electrochemical polymerization process. And they are readily modified into aligned nanostructure that might enhance charge transport and surface area simultaneously (Sun et al., 2015a). 

Keywords Polypyrrole, inorganic nanomaterials, nanocomposites, electrode materials, supercapacitors... 

Jang, J.S., X.L. Li, and J.H. Oh. 2004. Facile fabrication of polymer and carbon nanocapsules using polypyrrole core/shell nanomaterials. Chem Commun 794. 

Keywords Conducting polymer Nanomaterial Polyaniline Polypyrrole... 

An alternative to in situ polymerization involves direct intercalation of macromolecules into layered structures. Silicates are most often used. The insertion of polymer molecules into layered host lattices is of interest from different points of view. First, this insertion process leads to the construction of organic-inorganic polylayered composites. Second, the intercalation physical chemistry by itself and the role intercalation plays in the gain of electronic conductivity are of interest. This becomes important in the construction of reversible electrodes " or when improving the physicomechanical properties of nylon-layered silicate nanocomposites, hybrid epoxide clay composites," and nanomaterials based on hectorite and polyaniline, polythiophene or polypyrrole. ... 

FIGURE 17.10 Nanowires and nanotubes produced by the template method in an alumina template, (a) TEM micrograph of Au nanowires with a 70 nm diameter, (b) TEM micrograph of polypyrrole nanotubes. The outside diameter is about 90 nm, and the inside diameter is 20-30 nm. (Reprinted with permission from Martin, C.R., Membrane-based synthesis of nanomaterials, Chem. Mater., 8, 1739-1746, 1994. Copyright 1996 American Chemical Society.)... 

Prakash et al. who pioneered the studies utilising hemin modified sensors have also reported on the use of nanomaterials, namely copper nanoparticle modified SWCNTs-polypyrrole (PPy) nanocomposite modified Pt electrode Fig. 16.10 shows a schematic of how the electrode is produced. The sensor utilises the electrocatalytic activity of the copper nanoparticle electrode towards NOx which is fourfold times more than the just CuNP-PPy-Pt electrode. A linear dependence towards NOx concentrations ranging from 0.7 to 2,000 pM, with a sensitivity of 0.22 0.002 pA pM cm and detection limit of 0.7 pM, was reported. ... 

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