I. Yu. Sapurina

Oxidation of aniline with strong and weak oxidants

Oxidative polymerization of aniline by the action of a strong oxidant, ammonium peroxodisulfate, and a weak oxidant, silver nitrate, was studied in media with different acidities. Depending on the reaction conditions, the organic fraction of the products contained either nonconducting aniline oligomers or conducting high-molecular polyaniline. The effect of the oxidation potential on the oxidation process and formation of supramolecular structures by oxidation products was discussed on the basis of analysis of the kinetics and products of aniline oxidation by spectroscopic, conductometric, thermogravimetric, chromatographic (gel permeation), and electron microscopic methods. A relation was revealed between the morphology of composite materials and their electric conductivity.

Nanocomposites with Mixed Electronic and Protonic Conduction for Electrocatalysis

Novel multipurpose electrode materials that have various catalytic applications are developed. The materials are composites based on multiwalled carbon nanotubes and electroconducting polymer polyaniline, organized as “fiber in a jacket.” Nanoparticles of metallic platinum and compounds of transition metals are additionally immobilized in the polymer layer. It is demonstrated experimentally that the materials possess high electronic and protonic conductance, thermal stability, hydrophilicity, large specific surface area, and considerable porosity.

Properties of proton-conducting Nafion-type membranes with Nanometer-thick polyaniline surface layers

The study is directed to the improving of proton-conducting Nafion-type membranes for using in fuel cells with direct oxidation of liquid fuels. Nanometer-thick layer of polyaniline (in its conducting emerald-dine form) was deposited onto the membrane surface by in situ polymerization. The structure of the polyaniline layer is studied, as well as the properties of thus modified membranes (electronic and proton conduction, permeability for methanol, thermal stability). A method of platinum catalyst deposition onto the Nafion-modifying polyaniline layer is developed.

Self-Organization and Dynamic Characteristics Study of Nanostructured Liquid Crystal Compounds

Fullerene-doped liquid crystal compounds have been considered as new nanostructured materials with promising photosensitivity and speed parameters. Self-organization in liquid crystal mesophase based on charge-transfer complexes between an organic donor and fullerene has been investigated. The switch-on time of 50 μs has been obtained. The results are discussed from the viewpoint of increasing the system polarizability and a possible transition from the nematic phase to the smectic one, which is caused by a complex formation.

Carbon supported polyaniline as anode catalyst: Pathway to platinum-free fuel cells

The effectiveness of carbon supported polyaniline as anode catalyst in a fuel cell (FC) with direct formic acid fuel oxidation is experimentally demonstrated. A prototype FC with such a platinum-free composite anode exhibited a maximum room-temperature specific power of about 5 mW/cm2.

A conducting composite of polyaniline and wood

Production of a new conducting composite material based on polyaniline and wood by simple one-stage synthesis from aniline and wood sawdust is described. The material characteristics were studied in relation to the synthesis conditions and composition.

Polyaniline composites with fullerene C60

Polyaniline-fullerene composites were prepared by the introduction of fullerene during polymerization of aniline. An investigation of the composites using FTIR and 13C NMR spectroscopy indicated interaction between fullerene and the imine groups of polyaniline. The formation of a polyaniline-fullerene complex with a structure corresponding to a doped polyaniline was proved by wide-angle x-ray scattering analysis. The conductivity of composites is more than four orders of magnitude higher than that of undoped polyaniline and that of fullerene. Improvement in the thermal stability of composites was evaluated using TGA.

Deposition of polyaniline layers with controlled thickness and morphology by in situ polymerization

Method for deposition of layers of the organic semiconductor polyaniline onto various kinds of supports was developed. The method enables control over the layer thickness and morphology. It is based on formation of a polymeric layer on the support in the course of a heterophase in situ polymerization of aniline. Processes of self-organization of polymer chains on a support and their dependence on the in situ polymerization conditions were studied. Characteristics of polyaniline layers of varied morphology on different kinds of supports were analyzed by electron microscopy, spectroscopy, and conductometry.

Organic Nanocolloidal Polyaniline Dispersions Containing Fullerene

Abstract Polyaniline‐fullerene (C60) composites with nanoscale level ordered structure were prepared by the interfacial polymerization of aniline hydrochloride in water‐benzene emulsion containing fullerene. UV‐visible spectra, FTIR spectra and wide‐angle X‐ray diffraction were used to characterize the resulting materials. The luminescence measurements suggest the formation of a complex between conducting polymer and fullerene.

Nanostructures of Oligoaniline and Polyaniline and Their Properties

A conductive polymer, polyaniline, has been synthesized in the form of nanoparticles of different morphology: globules with a size of 100 nm, nanotubes with an outer diameter of 200 nm and a wall thickness of 50 nm, microspheres with a diameter of 2 μm, and hierarchical structures consisting of fibers with a diameter of 10 nm. All types of nanostructures have been prepared by single-stage oxidation of aniline under different synthesis conditions. The properties of nanostructures of polyaniline and the possibilities of their practical application have been discussed.