Polyaniline intercalation

Figure 6.13 FTIR of(polyaniline)o JHT1O2. (Reprinted with permission from Synthetic Metals, An intercalated polyaniline-titanate nanomaterial by 5. F. Scully and R. Bissessur, 159, 7-8 637-641. Copyright (2009) Elsevier Ltd)...

Bz3Sn(NCS)(OAsPh3) shows 5 coordination with isothiocyanate and arsine oxide axial and the Sn-N bond 232.5 pm, while that in (PhMe2Si)3CSnMe2NCS is tetrahedral about Sn with Sn-N 212 pm . The 3D trimethylstannyl hexacyanoferrates(III) intercalate polyaniline and the mixed Fe-Co derivative incorporate pyrrole to give polypyrrole, while [(Me3Sn)4M(II)(CN)6] (M=Fe, Ru, Os) show 3 equally abundant, non-equivalent CN ligands and 2 equally abundant,... 

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],... 

As our quantum-chemical calculations show, similar transformation and delocalization of bonds takes place in the conductive forms of some other types of CPs (polyaniline, polypyrolle, etc.). Delocalization of chemical bonds after activation leads to appearance of an electronic conductivity in such types of conducting polymers and creates prerequisites for their application as electrode materials of electrochemical power sources. Such activation can be stimulated by intercalation of ions, applying the potential, and by use of some other low energetic factors. 

The benefit of a hybrid phase for the intercalation-deintercalation of mobile species such as Li+ cations is well illustrated by the study of conductive polymers such as polyaniline or polypyrrole intercalated into a V2O5 framework as potential electrode materials in lithium batteries [34]. For PANI/V2O5, an oxidative post-treatment performed under an oxygen atmosphere allowed the authors to compare the conductivity attributed to the polymer, as in absence of reduced cations, there was no electronic hopping between ions, and the conductive state was due only to the... 

Intercalation of polyaniline between MoS2 layers produced nanoscale molecular composites with unusual charge transport properties [119]. Recent advances in the preparation, characterization, and utilization of conducting polymers intercalated into layered solids were surveyed [120],... 

Recently, new types of organic positives, formed by a mixture of dimercaptan with polyaniline, have been reported. These composite materials appear to have an energy density higher than that of most inorganic intercalation oxides and good cyclability. However, use of these materials in practical rechargeable lithium batteries has still to be confirmed. 

The organotin cyanometallates were also used to intercalate a range of organic compounds such as thiazole and benzothiazole derivatives, polyaniline or... 

Leroux F, Koene BE, Lazar LF. Electrochemical lithium intercalation into a polyaniline/V205 nanocomposite. J Electrochem Soc 1996 143 L181-L183. 

Challier, T. and Slade, R. C. T. (1994). Nanocomposite materials - polyaniline-intercalated layered double hydroxides. J. Mater. Chem. 4, 367. 

Encapsulation chemistry similar to that described above (exchange of anilinium, followed by oxidation with peroxydisulfate) was foimd to produce polyaniline not only in zeolite Y, but also in montmorillonite clay. 5 Spectral features (UV-VIS, IR and EPR) of the products were indicative of emeraldine salt and base formation, respectively. The change in basal spacing of the montmorillonite upon intercalation provided additional evidence for the inclusion polymerization. 

Intercalation of electroactive polymers such as polyaniline and polypyrrole in mica-type layered silicates leads to metal-insulator nanocomposites. The conductivity of these nanocomposites in the form of films is highly anisotropic, with the in-plane conductivity 10 to 10 times higher than the conductivity in the direction perpendicular to the film. Conductive polymer/oxide bronze nanocomposites have been prepared by intercalating polythiophene in V2O5 layered phase, which is analogous to clays. °° Studies of these composites are expected not only to provide a fundamental understanding of the conduction mechanism in the polymers, but also to lead to diverse electrical and optical properties. 

Modern inelastic neutron scattering technique has made it possible to discover free protons in solids [49] that is, free protons have been found in manganese dioxides, coals, graphite nitric acid intercalation compounds, polypyrolles and polyanilines, and fi-alumina. Perhaps the said compounds may be called protonic conductors as well, though in the solids the density of free protons is very small and the distribution of proton kinetic momentum is hidden by the zero-point oscillations of the host matrix [49]. 

Challier and Slade [175] reported the synthesis of nanocoinposite materials consisting of polyaniline molecules encapsulated between ultra-thin mixed metal hydroxide sheets which are propped apart by spacers of terephthalate or hexacyanoferrate(II) ions acting as pillars. The layered double hydroxides (LDHs) were prepared by the method of Drezdon [176] which were refluxed with aniline to synthesize aniline intercalated LDHs. In thermo-gravimetric studies, terephthalate/Cu/Cr LDHs as well as hexa-cyanoferrate(lI)/Cu/Al LDHs showed weight losses in two steps attributed to the removal of trapped water and thermal breakdown of the intercalated systems. The former material exhibited somewhat better thermal stability than the latter one. 

Figure 6.2 XRD of (A) FeOCI (B) (Ci6H33f H2)o.5FeOCI (C) (PANI)o.42FeOCI. (Reprinted with permission from Journal of Materials Chemistry, Synthesis of polyaniline-intercalated layered materlalsvia exchange reaction by Y. Matsuo, S. Hihashika, Y. Miyamoto et al., 12, 1592-1596. Copyright (2002) Royal Society of Chemistry)...

Similarly to FeOCl, V205.nH20 is also capable of undergoing in situ intercalation/ polymerization. The intercalation of polyaniline, polypyrrole, and polythiophene into... 

The hydrothermal synthesis of polyaniline-V205 nanocomposites with nanosheet morphology has been reported by Zhang and coworkers [34]. Reacting V2O5 powder with aniline, in the presence of water and hydrochloric acid, in an autoclave at 120°C for 24 hours resulted in the formation of polyaniline-V2O5 intercalated... 

Ternary composites with electroactive components were also discussed by Gomez-Romero and coworkers in one of their recent publications [48]. The ternary composites consisted of doped-polyaniline (PANI) or doped-polypyrrole (Ppy) intercalated into V2O5 xerogels. The dopant anion for the conducting polymers was [Fe(CN)g] (HCF), derived from H3Fe(CN)6. More specifically, the synthesis of Ppy/HCF/V205 and PANI/HCFA 20s was carried out by treating the monomer (aniline or pyrrole)... 

It is also interesting to note that polyaniline doped with camphor sulfonic acid (PANl-CSA) was intercalated into M0O3. This was achieved by adding PANI-CSA dissolved in m-cresol to an aqueous sol of LixMo03- The stoichiometry of the intercalate as determined from elemental analysis was (PANI-CSAo.i24)i 06M0O3. Evidence of intercalation was obtained from powder X-ray diffraction [59]. 

Using a one-pot reaction design, an intercalated compound of polyaniline into M0O3 was prepared by Shao et al. [60]. This particular method of synthesis uses a coprecipitation route to fabricate the layered structure. An excess of aniline was acidified to a pH of 0.5, to which was added ammonium molybdate [(NH4)gMo7024.7H20] and FeCl3. The powder pattern of the isolated product revealed the formation of an intercalated phase of polyanihne into M0O3. The identity of the entrapped polymer was confirmed by FTIR... 

The intercalation of polyaniline into hydrogen uranyl phosphate HUO2PO4.4H2O (HUP) was reported by Liu and Kanatzidis [67]. HUP is a layered material with an interlayerspacing value of 8.69 A. The layers consist of dumb-bell-shaped UO2 ions with uranium further coordinated to four equatorial oxygen atoms of four P04 tetrahedra. The van der... 

The intercalation of PANI in zirconium phosphate (ZrP) was also reported by Chang et al. [69]. Different phases of zirconium phosphate, such as y-ZrP, the dihydrogen form of a-ZrP [o -ZrP(HH)], and o -ZrP(NaNa), were intercalated with aniline by either ion-exchange or adsorption, and then polymerized by oxidizing agents such as ammonium peroxydisulfate and iron (III) chloride. The resulting polyaniline nanocomposites showed measurable electrical conductivities, as listed in Table 6.3. 

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