Polypyrrole nanofibers

FIGURE 16.4 I-V characteristics of iodine doped PA nanofiber. Znsef shows scanning force microscope image of PA nanofiber on top of Pt electrodes (with 100 nm separation). Typical diameter of PA nanofiber is 16-20 mn (From Park, J.G., et al. Synth. Met., 119, 53, 2001 and Park, J.G., Electrical transport properties of conducting polymer nanostructures Polyacetylene nanofiber, polypyrrole nanotube/nanowire, Ph.D. thesis, Seoul National University, Seoul, 2003.). 

Park, J.G. 2003. Electrical transport properties of conducting polymer nanostructures Polyacetylene nanofiber, polypyrrole nanotube/nanowire. Ph.D. thesis, Seoul National University, Seoul. 

Although we have been able to electrospin polyaniline into nanofibers, polypyrrole is unable to be processed into homogenous textile fibers since this ICP is insoluble in common organic solvents and infusible, thus making thermal or solution processing difficult. To overcome this limitation. 

Polymers consisting of but not limited to poly thiophene, polypyrrole and poly aniline have been extensively used to make polymer nanofibers. In general, any metal that can be electroplated has most likely appeared in a nanowire. Semiconductors, polymers, and insulators have also been used in the design of nanowires.Furthermore, different metals can be plated in succession to give striped nanowires. 

Li M, Wei ZX, Jiang L (2008) Polypyrrole nanofiber arrays synthesized by a biphasic electrochemical strategy. J Mater Chem 18(19) 2276-2280... 

Figure 4.10 SEM micrographs of electrospun nanofibers from (a) aqueous solutions of 1.5 wt% PEO as carrier with PPy content of 71.5 wt%, (b) 7.5wt% [(PPy3) (DEHS) ]x solution in DMF. The scale bar is Igm. (Reprinted with permission from Polymer, Conductive polypyrrole nanofibers via electrospinning Electrical and morphological properties by I. S. Chronakis, S. Grapenson and A. Jakob, 47, 1597-1603. Copyright (2006) Elsevier Ltd)...

A novel route to pure and composite fibers of polypyrrole was recently reported by Han and Shi [42]. An organic salt (FeAOT) was synthesized by the reaction of sodium l,4-bis(2-ethyUiexyl)sulfosuccinate (AOT) and ferric chloride. It was fabricated into nanofibers by manual drawing and electrospinning. Long PPy fibers were obtained for the first time by a vapor deposition reaction of pyrrole on the FeAOT fibers, and this technique was extended to the synthesis of PPy composite fibers with multiwalled carbon nanotubes (PPy-MWCNT fibers). The PPy and PPy-MWCNT fibers had a nanoporous morphology, a conductivity of 10-15 S cm and a tensile strength of 12—43 MPa. Studies of the electrochemistry and current-voltage characteristics of the PPy fibers were also reported. 

Figure 4.12 Schematic illustration of the mechanism for preparing core-shell nanostructured conductive PPy composites. (Reprinted with permission from Materials Letters, Fabrication of Polyacrylonitrile/polypyrrole (PAN/Ppy) composite nanofibers and nanospheres with core shell structures by electrospinning by X. Li, X. Hao, H. Yu and H. Na, 62, 1155-1158.

I. S. Chronakis, S. Grapenson, and A. Jakob, Conductive polypyrrole nanofibers via electrospinning electrical and morphological properties. Polymer, 47, 1597-1603 (2006). 

S. Nair, S. Natarajan, and S. H. Kim, Fabrication of electrically conducting polypyrrole-poly(ethylene oxide) composite nanofibers, Macromolec. Rapid Commun., 26, 1599-1603... 

F. Granato, A. Bianco, C. Bertarelli, and G. Zerbi, Composite polyamide 6/polypyrrole conductive nanofibers, Macromolec. Rapid Commun., 30, 453 58 (2009). 

S. Nair, E. Hsiao, and S. H. Kim Fabrication of electrically-conducting nonwoven porous mats of polystyrene-polypyrrole core-shell nanofibers via electrospinning and vapor phase polymerization, J. Mater. Chem., 18, 5155-5161 (2008). 

Y-W. Ju, J-H. Park, H-R. Jung, and W-J. Lee, Electrochemical properties of polypyrrole/ sulfonted SEBS composite nanofibers prepared by electrospinning, Electrochim. Acta, 52, 4841 847 (2007). 

L. Al-Mashat, H.D. Tran, W. Wlodarski, R.B. Kaner, and K. Katantar-Zadeh, Conductometric hydrogen gas sensor based on polypyrrole nanofibers, IEEE Sens. J., 8, 365-370 (2008). 

Figure 16.17 Schematic illustration of two-phase electropolymerization (a) Pyrrole diffuses from the organic phase into the aqueous phase slowly (indirect diffusion). Then polypyrrole is deposited by the diffusion of pyrrole to the electrode (direct diffusion), (b) Aligned polypyrrole nanofibers are produced by successive CV electropolymerizations. (Reprinted with permission from Journal of Materials Chemistry, Polypyrrole nanofiber arrays synthetized by a biphasic electrochemical strategy by M. Li, Z. Wei and L. Jiang, 18, 2276-2280. Copyright (2008) Royal Society of Chemistry)...

With successive cyclic voltammetric (CV) electropolymerizations, the length of the polypyrrole nanofibers could be controlled from several hundred nanometers to several micrometers (Figure 16.18). 

Figure 17.6 FESEM images of polypyrrole nanofIber network (a) Low magnification image and (b) edge view of the polypyrrole nanofiber network. High magnification images of polypyrrole nanofiber network formed at (c) 120 s and (d) 1 b. (Reprinted with permission from Macromolecules, Template-Free Electrochemical Synthesis of Superhydrophilic Polypyrrole Nano fiber Network by J.F. Zhang, C. M. Li, S.J. Baoetal.,41, 19, 7053-7057. Copyright (2008) American Chemical Society)...

Du, Z.J., Zhang, S.C., Liu, Y, Zhao, J.E, Lin, RX, Jiang, X, 2012. Facile fabrication of reticular polypyrrole-siUcon core-sheU nanofibers for high performance lithium storage. J. Mater. Chem. 22,11636-11641. 

Alternating current has also been used to stimulate the growth of PC12 cells on conducting scaffolds made of polyfcaprolactone fumarate)-polypyrrole (PCLF-PPy). PC 12 cells were cultured on PCLF-PPy scaffolds and alternating current of 10 pA amplitude and 20 Hz frequency was applied to the cell-seeded scaffold everyday for Ih [31]. Similarly, fluorescent microscope helps in the imaging of fibroblast cells that were cultured on PHBV nanofibers after 48 h of culture (Figure 2.2). 

Abbreviations AC, activated carbon HPCs, hierarchically porous carbons GO, graphene oxide PPy, polypyrrole CNTs, carbon nanotubes CNFs, carbon nanofibers rGO, reduced graphene oxide and NWs, nanowires. 

Shi, K. Y., and I. Zhitomirsky. 2013. Polypyrrole nanofiber-carbon nanotube electrodes for supercapadtors with high mass loading obtained using an organic dye as a co-dispersanL Journal of Materials Chemistry A 1 11614-11622. 

Scott, C. L., Zhao, G., and Rumera, M. [2010]. Stacked graphene nanofibers doped polypyrrole nanocomposites for electrochemical sensing, Electrochem. Commum, 12, pp. 1788-1791. 

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