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A novel flexible electrospun nanofiber/γ-Fe₂O₃ composite has been obtained from suspension of γ-Fe₂O₃ nanoparticles in polyvinylpyrolidone solution in dimethylformamide. The impedance spectroscopy of the synthesized nanofiber/γ-Fe₂O₃ composite was carried out. Negative magnetoresistance and giant magnetocapacitance effects, as well as phenomenon of a "negative capacitance" at room temperature were observed in magnetic field (2.75 κOe) in infra-low frequency range. The polarization properties and volt-ampere characteristics of the nanocomposite in the applied magnetic field indicate the increase in the dielectric permittivity ɛ and the emergence of spin electromotive force, which enables us to accumulate of electric energy at quantum level. A quantum-mechanical model, which explained the non-monotonous behaviour of the volt-ampere characteristic of the novel nanofiber based composite, has been suggested.

Two-dimensional nanofiber mats based on a mixture of polybenzimidazole with telechelic oligoperoxide are obtained by the method of electrospinning. It is shown that the reactive peroxide groups on the surface of nanofibers can be modified by the initiation of radical polymerization and grafting of various polymeric chains. The phenomenon of “negative” capacitance is detected for the impedance dependences of synthesized nanofibers. The influence of grafting of various polymeric chains to the surface of nanofibers on the polarization characteristics of nanocomposites is investigated. It is shown that some of the obtained structures are characterized by a combination of a low (< 1) tangent of dielectric losses in the infralow-frequency region (0.001–0.1 Hz) and high values of the dielectric permittivity (∼106). The possibilities of application of materials of this kind in the production of quantum batteries are discussed.

A new technological approach to the synthesis of multilayer nanostructures which allows their use in high-performance storage of electrical energy at the nanoscale level is discussed in this paper. In particular, the effect of co-intercalation of histidine (his), water and a solution of KOH into layered semiconductors of GaSe and InSe on the charge accumulation are studied. Based on the data of the cyclic current-voltage characteristics (CVC) a power storage mechanism (capacitive/pseudocapacitive) in each of these structures is described. This mechanism is in a good accord with the results of galvanostatic studies. The simulation of the parameters of the impedance equivalent circuit has been carried out, proving the possibility of using the described structures for nanoelectronics and nanoenergy devices. The observed values of tangent of electrical losses tgδ (

The purpose of this work is to expand the class of electrical energy storage devices with non-conjugate functional hybridity. Cyclodextrins of β- and γ-modifications has used as a starting material for research. These materials containing intramolecular voids, which are able to accommodate guest components by molecular recognition on the "lock-key" principle. Methods of precision porometry and impedance spectroscopy has used to study the obtained carbon structures, electrochemical and magnetic measurements has performed to study the obtained carbon structures. Data of the precision porometry has indicated a bimodal porous structure of the synthesized chars. The total specific surface area of active surface of the β-cyclodextrin carbonizate was about 72 m2/g. After KOH-modification, the specific capacity for β-cyclodextrin char was 158 F/g, and in the negative potential range – 203 F/g. The last value for γ-cyclodextrin carbon was 162 F/g. The ability of β-cyclodextrin to molecular recognition of ferrocene (FC) has used and this cavitat has subjected to activation carbonation according to the same modes as β-cyclodextrin. The specific capacity of the obtained char of the β-CD complex after the KOH-modification was 110 F/g, the specific capacity of the cavitate carbon synthesized on γ-CD has dropped twice. The study of complexes host-guest inclusions β-cyclodextrin with molecular iodine has indicated a slight increase of capacity. However, their interface with 30 % aqueous electrolyte solution has shown high photosensitivity. The specific capacitance of the cavitate carbon without KOH-modification has increased four times when it was illuminated with integral and monochromatic light from LEDs of the same intensity. Magnetic studies of the synthesized carbonates have shown that they all demonstrate ferromagnetic properties. Measurement under normal conditions and in a constant magnetic field of cells of symmetric configuration on carbon-based electrodes synthesized with γ-CD and γ-CD has showed that their capacitance practically does not change, but their reactance parameters change significantly. Supercapacitors based on these carbonates can serve as sensors of a weak magnetic field at room temperature. Magnetovarionistors is a new class of devices, which are forming on such kind of supercapacitors.

Molybdenum disulfide is obtained by the template method. Its structure and electrochemical properties are investigated. It was found that the working voltage of the LPS for molybdenum disulfide obtained by template method reaches 3 V, the specific capacitance is 180.9 F/g. It was identified that the electric energy storage device the positive electrode of which is molybdenum disulfide obtained by the template method has the discharge specific capacity of 238.9 F/g at a scan rate of 0.001 V/c.

The dielectric constant and the loss tangent of such nanostructured materials as MCM-41 with encapsulated into its pores, the ferroelectric liquid crystal (LC) or rhodamine 6G and B dyes, as well as the characteristics of the intercalated GaSe by the L-aspartic acid (LAA) are investigated. Influence of microwave irradiation on characteristics of the MCM-41 nanohybrid and impact of illumination along the crystallographic c-axis on the GaSe nanostructure are described.

We have found that the structures based on ITO/tri(9-hexylcarbazol-3-yl)amine/Ca/Al fabricated by means of vacuum deposition generate acoustic oscillations when pulse voltage is applied. Impedance spectroscopy study indicates the presence of significant inductive response, which is the result of significant energy barriers at the semiconductor-metal interface. We assume that a very heterogeneous spatial distribution of the electric field at the organic/metal interface and the noncoplanarity of the molecules cause the electrostriction effect in the structures.

Three types of nanohybridized structures such as organic/dielectric, organic/semiconductor, and organic/graphen-like ones are investigated. The effect of ultrasonic exposure on the material structure and its influence on the dielectric permeability and on the dielectric loss tangent are studied for the first type of nanostructures. The magnetoresistance of a structure at room temperature is studied in the second type of materials. The change of the kinetic parameters of the intercalation process is shown for the third type of nanohybrid structures.

We performed impedance spectroscopy studies on intercalated multilayer structures of type-layered inorganic semiconductor (gallium selenide and indium selenide)/organic semiconductors (N,N′-dimethyl-3,4,9,10-perylenetetracarboxylic diimide), which revealed the appearance of low-frequency inductive response as a result of intercalation of organic semiconductors (OS) into inorganic semiconducting layers. A current–voltage characteristic has the shape of Coulomb steps with a step 0.32 V that are blurred due to superimposition of electric field and illumination. An applied electric field and illumination during the introduction of OS leads to the formation of electrets and photoelectret states that modify polarisation and photoprocesses in accordance with the conductivity type of nonorganic matrix.

Impedance spectroscopy studies performed for intercalated multilayer structures of the type of a layered inorganic semiconductor (InSe)/conducting polymer (PEDOT:PSS) revealed low-frequency inductive response and the growth of dielectric permeability in megahertz region together with the decrease of dielectric loss angle down to one as a consequence of the conducting polymer intercalation into semiconducting layers. A model describing the unusual current–voltage characteristic is proposed.

We report on stable in time organic photovoltaic devices based on metal-phthalocyanine structures, which were formed by vacuum deposition of nickel phthalocyanine (NiPc). The reported stability is due to ultra-thin zinc oxide (ZnO) layer formed at low temperature on top of the structure (beneath the metal contact) by atomic layer deposition (ALD) technique. We performed comparative analysis of current density–voltage characteristics and frequency dependencies of the impedance for freshly made ITO/NiPc/ZnO/Al and ITO/NiPc/Al devices and after storage during one month in air. We conclude that introducing of ultra-thin ZnO film into under-cathode region of ITO/NiPc/Al structure provides long-term protection of NiPc films from atmospheric effects.

Within the framework of the Kronig-Penny model, changes in the electron spectrum of a layered crystal caused by intercalation are analyzed. Special attention is paid to both the geometric changes of the crystal and its energy characteristics during intercalation. The extraordinary behavior of the spectrum caused by the geometric intercalation factor is observed.

Double-matrix hierarchical structure of the 〈molecular-lattice matrix MCM-41〈hydroquinone〉〉 is synthesized. Its use in the cathode process in the Li +-intercalation current generation showed a significant improvement in the structure of the discharge curve and the practical constancy of diffusion coefficient throughout the discharge process. Theoretical model describing the peculiarities of observed characteristics in the structure is presented.

Heterophase nanostructures with alternate semiconductor and electrolytic seams are received. It is shown that the insertion of a polymer composition into the van der Waals gap of crystals causes the additional potential barriers in them. A non-monotone change of the resistance of the obtained structure under applied potential, as well as the strong low-frequency dispersion, has been found out, which can be due to the polarization of double electric layers.