L. A. Zemskova

Atomic force microscopy and X-ray photoelectron spectroscopy study of chitosan-carbon fiber materials

Chitosan-carbon materials produced by electrochemical deposition of chitosan on an activated carbon fiber (ACF) as an electrode have been studied by atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). AFM data demonstrate that the microstructure of the coating depends on whether chitosan is deposited in soluble or insoluble form. XPS data are used to evaluate the state of chitosan in the composites in relation to the deposition conditions.

Manganese oxide carbon fibrous materials

Changes in electrochemical properties and surface morphology of carbon fibrous materials upon modification with manganese oxides under various conditions of their deposition were studied. The composition of manganese oxides was determined. The capacitances of the electrical double layer of manganese oxide carbon fibrous materials in sodium chloride solutions of various concentrations were found. Charging parameters of the modified electrodes were determined.

Rhenium Sorption by Fibrous Chitosan-Carbon Materials

We studied equilibrium and kinetic characteristics of rhenium sorption by Busofit-based fibrous carbon materials (FCMs) treated electrochemically with recovery potentials varying from −900 to +600 mV from aqueous solutions in the presence of natural biopolymer chitosan. Materials obtained in the anodic potential region and at the open-circuit potential have the best capacity characteristics. The highest rhenium capacity is observed for the material prepared at the recovery potential +600 mV. The relevant sorption isotherm is described by the Langmuir equation with the constant 73.0 ± 8.1 mL/mg; the half-conversion time is 3 min.

Correlation of electrochemical and structural characteristics of chitosan-carbon fibrous materials

Changes in the electrochemical properties and morphology of the surface of fibrous materials in the course of their modification with chitosan were studied in relation to the conditions of biopolymer deposition. The capacitances of the electrical double layer of the chitosan-carbon materials in NaCl solutions of various concentrations were determined by of cyclic voltammetry and the method of charging curves. The parameters of charging of the modified electrodes were calculated.

Relationship between electrochemical and structural properties of modified carbon fibers

Effect of modification conditions on the electrochemical and structural properties of fibrous carbon materials was studied.

Study of the formation and electrochemical properties of nickel oxide-carbon fiber composites obtained in the presence of surfactants

The electrochemical properties of nickel oxide-carbon fiber composites obtained in the presence of SDS and PEG surfactants and chitosan biopolymer by means of cyclic voltammetry have been investigated. The material’s capacity parameters have been determined and the charging times and electrolyte resistance in pores have been calculated. The interrelation between the electrochemical and structural composite parameters are demonstrated.

Effect of modification on electrochemical and sorption properties of woven carbon materials

Relationship between electrochemical, structural, and sorption properties of woven carbon materials modified with chitosan was studied.

INFLUENCE OF MODIFICATION ON THE ELECTROCHEMICAL PROPERTIES AND THERMAL OXIDATION STABILITY OF CARBON FIBERS

The electrochemical and thermal properties of composites prepared from carbon fiber modified by chitosan deposited on the fiber surface in various forms were investigated. The electrochemical behavior of a composite modified with chitosan in the sulfate form differed from that of starting carbon fiber and composites modified by electrochemical deposition of chitosan. The preparation conditions and subsequent electrochemical treatment affected the thermal oxidative stability of the composites. It was noted that cyclic cathodic-anodic and then cathodic treatment of the composites degraded them significantly. Cyclic voltammetry could be used to assess the surface condition of fibers modified with chitosan.

Functional materials based on manganese dioxide deposited on carbon fiber

The composites manganese oxide/carbon fiber are obtained by chemical and electrochemical deposition. The process of electrodeposition was carried out in the presence of tetraalkylammonium cations of neutral SAA Triton X-100 in a potentiostatic regime by oxidating Mn2+ salts at +1.0 V (with respect to Ag/AgCl). Cathodic deposition was carried out in aqueous electrolytes NH4Cl and KCl and in the presence of polyelectrolyte of chitosan with oxidation of the formed precipitates by oxygen in air. The obtained composites are characterized by scanning electron microscopy, X-ray diffraction, and cyclic volt-amperometry techniques. The mechanism of film formation at the surface of the carbon fiber and the electrochemical properties of the composites are discussed.

Organic-Mineral Composites Copper Oxide/Chitosan/Carbon Fiber Obtained by the Electrodeposition Method

The methods of the coprecipitation of chitosan and copper-containing particles on a carbon fiber used as a cathode and also of the precipitation of copper(II) on a carbon-fiber electrode preliminarily modified by chitosan were studied for feasibility of obtaining composites containing copper oxide/copper in a chitosan matrix. The composition, morphology, structure of the organic-mineral composites were studied by the methods of X-ray phase analysis, scanning electronic microscopy, X-ray photoelectron spectroscopy, and ESR spectroscopy.