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Under well-controlled electrochemical conditions, C 60 -Pd polymer was deposited at the electrode surface in tetra-n-butylammonium acetonitrile/toluene solution. The electrochemical properties and conductivity of this material were studied in acetonitrile containing different tetraalkylammonium perchlorates as supporting electrolytes. The film exhibits n-doped properties. The electrochemical quartz crystal microbalance results reveal that the polymeric film is doped with cations of the supporting electrolyte during switching between the neutral and reduced states. Such a transition also results in a sharp increase of the film conductivity. The C 60 -Pd doping level and, therefore, charge carrier density depend on the size of the counterions incorporated into the polymeric structure during its reduction. The conductivity of the C 60 -Pd polymeric film also depends on the size of the doping cation. The negatively charged mobile carriers generated during the film reduction are responsible for the film conductivity. The charge propagation through the polymeric film can be quantitatively described by the electron-hopping model. The specific conductivity of C 60 -Pd and the electron diffusion coefficient are of the same order of magnitude as the values reported for typical p-doped conducting polymers. The conductivity properties of the composite of C 60 -Pd polymer and palladium nanoparticles were also investigated. Metallic nanoparticles participate in charge transport within the film in the potential range of the polymer neutral state. Therefore, the C 60 -Pd/Pd composite exhibits a large potential window of the conductivity state. The conductivity components related to the palladium nanoparticle involved in the charge transfer process and the electron hopping between differently charged fullerene centers were separated and determined.

A gold electrode modified with a polypyrrole–mesoporous silica molecular sieves (polypyrrole—MCM-48) nanostructure film was used for the electrochemical determination of small concentrations of dopamine (DA) by cyclic voltammetry and square-wave voltammetry techniques. This electrode showed good electrocatalytic activity for the oxidation of dopamine. The oxidation potential of dopamine was decreased significantly compared with that obtained at the bare gold electrode. The observed linear range for the determination of the dopamine concentration, without interferents through cyclic voltammetry measurements, was from 10 μM to 1.2 mM (R2 = 0.9989) for the gold electrode modified with the polypyrrole—MCM-48 nanostructure, with a detection limit of 2.5 μM. In the case of square-wave voltammetry, the linear range was 2–250 μM, with a correlation coefficient of 0.9996, and the detection limit was estimated to be 0.7 μM. The effects of interferents, such as ascorbic acid (AA) and uric acid (UA), on the electrochemical detection of dopamine were also examined. The modified electrode can successfully separate the oxidation potentials for ascorbic acid and dopamine, shifting the oxidation peak potential of ascorbic acid to a more positive potential, and significantly decreasing the peak current. The presence of ascorbic acid increased the sensitivity of dopamine determination at the modified electrode, and the detection limit was estimated to be 0.5 μM with 0.1 mM ascorbic acid to imitate physiological solutions. Additionally, studies showed that the presence of uric acid does not affect the electrochemical detection of dopamine. The modified electrode can be successfully applied for the quantitative analysis of dopamine both with and without interferents.

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The trinuclear complex, Au(3)(MeN=COMe)(3), which displays a number of remarkable properties including solvoluminescence, has been found to undergo electrochemical oxidation with the deposition of long, thin needles on the electrode surface. The electro-deposition process has been studied by cyclic voltammetry, chronoamperometry, and quartz crystal microbalance techniques. The composition of the electrically conducting needles has been determined to be [Au(3)(MeN=COMe)(3)](ClO(4))(0.34) by two complementary methods. The related complex Au(3)(PhCH(2)N=COMe)(3) underwent oxidation at a significantly more positive potential and did not produce a deposit on the electrode surface.

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structure, which can be easily covalently modified. Progress in extensive organic chemistry of fullerene development facilitates the production of a variety of fullerene derivatives with different structures and physicochemical properties. Additionally, the polyhedral structure of fullerenes containing a large number of bonding sites provides an opportunity for a wide range of covalent modifications. Polymeric structures containing fullerene moieties represent a particularly large class of materials in terms of their number, composition, structure, morphology, and physicochemical properties. [24-29] Some of the most common structures of these polymeric materials are schematically shown in Figure 1. The simplest and most common structures are composites formed from the polymeric chains and fullerenes. Fullerenes form a crystalline phase in the polymeric matrix [30] or are incorporated as guest molecules into polymeric chain containing host moieties. [31] In both cases, covalent interactions are not formed between fullerenes and the polymeric network. However, van der Waals and electrostatic interactions, as well as possible charge transfer between both components of the composite significantly modulate the electronic structure of the polymer/fullerene interphase. [32,33] A stronger electronic interaction between the polymer component and fullerene moieties is expected for the system in which carbon cages are covalently bound to the polymeric chain or covalently incorporated into the polymeric backbone. In the case of in-chain structures, fullerene moieties are separated by short organic conjugated linkers, [34-37] small inorganic linkers, [37-39] or metal atoms and metal complexes. [7,8,29,40-42] A large group of fullerene-based materials consists of organic conducting polymers containing fullerenes attached covalently to the polymer chain by the linker. [43-46] The physicochemical properties of these materials depend on the polymer chain, linker structures, and the density of fullerene moieties within the polymeric material. Similar to olefins, fullerene form homopolymers through [2+2] cycloaddition. [47-51] Fullerene homopolymers, in-chain and side chain fullerene polymers can be cross-linked to form 3D polymeric structures. A large number of reactive π-bond centers in the fullerene moiety enable the formation of star-shaped macromolecular systems with polymeric chains covalently grafted to the C 60. [52-57] In common structures, the number of linked This article provides a comprehensive review of research related to the formation and electrochemical properties of fullerene-based conducting polymeric materials. The paper begins with an overview of composites containing fullerenes incorporated into the network of a conducting polymer through van der Walls, electrostatic, or guest-host interactions. The properties of these composites are generally a superposition of the properties of the individual components. More attention is devoted to the structures in which fullerene is covalently incorporated into the polyme...