Polyaniline nanoparticle

Figure 2.31 Schematic diagram of the immobilization and hybridization of DMA on Au/ nanoPAN/GCE. (Reprinted with permission from Analytica Chimica Acta, Enhanced Sensitivity for deoxyribonucleic acid electrochemical impedance sensor Gold nanoparticle/polyaniline nanotube membranes by Y. Eeng, T. Yang, W. Zhang, C. Jiang and K. Jiao, 616, 2, 144-151. Copyright (2008) Elsevier Ltd) (See colour Plate 1)...

X. Wang, T. Yang, Y. Feng, K. Jiao, and G. Li, A novel hydrogen peroxide biosensor based on the synergistic effect of gold-platinum alloy nanoparticles/polyaniline nanotube/chitosan nanocomposite membrane. Electroanalysis, 21, 819-825 (2009). 

Y. Ma, N. Li, C. Yang, and X. Yang, One-step synthesis of water-soluble gold nanoparticles/ polyaniline composite an dits application in glucose sensing, Colloids Surf. A, 269,1-6 (2005). 

Figure 17.9 Cyclic voltammograms of electrochemical oxidation of ascorbic acid (A) a planar film composed of PAN/Au-NPs (B) a planar film composed of PAN/PSS (C) a bare Au electrode, in different concentrations of ascorbic acid (a) 0 mM, (b) 5 mM, (c) 10 mM, (d) 20 mM, (e) 30 mM, and (f) 40 mM. The data were recorded in 0.1 M phosphate buffer, pH 7.5. Oxygen was removed from the background solution by bubbling Ar. Potential scan rate, 5 mV s (Reprinted with permission from Chemistry of Materials, Enhanced Bioelectrocatalysis Using Au-Nanoparticle/Polyaniline Hybrid Systems in Thin Films and Microstructured Rods Assembled on Electrodes by E. Granot, E. Katz, B. Basnar and I. Wiliner, 17, 18, 4600—4609. Copyright (2005) American Chemical Society)...

E. Granot, E. Katz, B. Basnar, and I. WiUner, Enhanced bioelectrocatalysis using Au-nanoparticle/polyaniline hybrid systems in thin films and microstrucmred rods assembled electrodes, Chem. Mater., 17, 4600-4609 (2005). 

Feng, Y, Yang,T, et al. Erihanced sensitivity for deoxyribonucleic acid electrochemical impedance sensor Gold nanoparticle/polyaniline nanotube membranes. Analytica chi-mica acta,616(2), 144-151 (2008). 

Chandrakanthi, R.L.N., and M.A. Careem. 2002. Preparation and characterization of CdS and CU2S nanoparticle/polyaniline composite films. Thin Solid Films 417 (1—2) 51—56. 

Figure 14. Au nanoparticle on polyaniline support with twin boundary (F. Klasovsky, P. Claus, unpublished results, 2006).

PP-g-MA) silicate nanocomposites and intercalated thermoset silicate nanocomposites for flame-retardant applications were characterised by XRD and TEM [333], XRD, TEM and FTIR were also used in the study of ID CdS nanoparticle-poly(vinyl acetate) nanorod composites prepared by hydrothermal polymerisation and simultaneous sulfidation [334], The CdS nanoparticles were well dispersed in the polymer nanorods. The intercalation of polyaniline (PANI)-DDBSA (dodecylbenzene-sulfonate) into the galleries of organo-montmorillonite (MMT) was confirmed by XRD, and significantly large 4-spacing expansions (13.3-29.6A) were observed for the nanocomposites [335],... 

Ganesan R, Shanmugam S, Gedanken A (2008) Pulsed sonoelectrochemical synthesis of polyaniline nanoparticles and their capacitance properties. Synt Met 158 848-853... 

Xia H, Cheng D, Xiao C, Chan HS (2006). Controlled synthesis of Y-junction polyaniline nanorods and nanotubes using in situ self-assembly of magnetic nanoparticles. J. Nanosci. Nanotechnol. 6 3950-3954. 

Qiu, J.-D., et al., Controllable deposition of a platinum nanoparticle ensemble on a polyaniline/graphene hybrid as a novel electrode material for electrochemical sensing. Chemistry - A European Journal, 2012.18(25) p. 7950-7959. 

Santhosh, P., A. Gopalan, and K.-P. Lee, Gold nanoparticles dispersed polyaniline grafted muttiwall carbon nanotubes as newer electrocatalysts Preparation and performances for methanol oxidation. Journal of Catalysis, 2006. 238(1) p. 177-185. 

The polymer resulting from oxidation of 3,5-dimethyl aniline with palladium was also studied by transmission electron microscopy (Mallick et al. 2005). As it turned out, the polymer was formed in nanofibers. During oxidative polymerization, palladium ions were reduced and formed palladium metal. The generated metal was uniformly dispersed between the polymer nanofibers as nanoparticles of 2 mm size. So, Mallick et al. (2005) achieved a polymer- metal intimate composite material. This work should be juxtaposed to an observation by Newman and Blanchard (2006) that reaction between 4-aminophenol and hydrogen tetrachloroaurate leads to polyaniline (bearing hydroxyl groups) and metallic gold as nanoparticles. Such metal nanoparticles can well be of importance in the field of sensors, catalysis, and electronics with improved performance. 

Liljeroth et al. [80] used SECM in the feedback mode to study the electronic conductivity of a film of gold nanoparticles deposited at various pressures on a nonconductive substrate. They were able to observe an insulator-to-metal transition associated with a change in surface pressure. Unwin Whitworth et al. [83] have also developed a method to determine the electronic conductivity of ultrathin films using SECM under steady-state conditions. They obtained analytical approximations for the fitting of approach curves. The usefulness of their approach was demonstrated by investigating the effect of surface pressure on conductivity of a polyaniline monolayer at the water-air interface. 

Cholli AL, Thiyagarajan M, Kumar J et al (2005) Biocatalytic approaches for synthesis of conducting polyaniline nanoparticles. Pure Appl Chem 77 339-344... 

Different electron-conducting polymers (polyaniline, polypyrrole, polythiophene) are considered as convenient substrates for the electrodeposition of highly dispersed metal electrocatalysts. The preparation and the characterization of electronconducting polymers modified by noble metal nanoparticles are first discussed. Then, their catalytic activities are presented for many important electrochemical reactions related to fuel cells oxygen reduction, hydrogen oxidation, oxidation of Cl molecules (formic acid, formaldehyde, methanol, carbon monoxide), and electrooxidation of alcohols and polyols. 

A different approach was taken by Kumar and associates [61]. Fie also embedded metals in polymers, but used as his precursor the polymer and not the monomer. In his first study a composite material containing amorphous Cu nanoparticles and nanocrystalline CU2O embedded in polyanUine matrices was prepared by a sonochemical method. These composite materials were obtained from the soni-cation of copper (II) acetate when aniline or 1% v/v aniline-water was used as the solvent. Mechanisms for the formation of these products are proposed and discussed. The physical and thermal properties of the as-prepared composite materials are presented. A band gap of 2.61 eV is estimated from optical measurements for the as-prepared CU2O in polyaniline. 

Metal nanoparticles housed in zeolites and aluminosilicates can be regarded as arrays of microelectrodes placed in a solid electrolyte having shape and size selectivity. Remarkably, the chemical and electrochemical reactivity of metal nanoparticles differ from those displayed by bulk metals and are modulated by the high ionic strength environment and shape and size restrictions imposed by the host framework. In the other extreme end of the existing possibilities, polymeric structures can be part of the porous materials from electropolymerization procedures as is the case of polyanilines incorporated to microporous materials. The electrochemistry of these types of materials, which will be termed, sensu lato, hybrid materials, will be discussed in Chapter 8. 

Coupling reactions. Pd nanoparticles supported on polyaniline fibers are catalytically active for Suzuki coupling. 2-Chlorobiaryls are obtainable from areaction of ArB(OH)2 with... 

For Suzuki coupling, amine ligands tested to support PdCl2 include polyaniline, 2-(2-pyridyl)-6-isopropylpiperidine, and piperazine The naphthidine 2 actually reduces PdCl2 to Pd(0) nanoparticles and stabilizes such to perform catalysis. ... 

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