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The impact of phase state of guest histidine on properties and practical applications of nanohybrids on InSe and GaSe basis

Ivashchyshyn F. O., Grygorchak I. I., Balaban O. V., Seredyuk B. O.

Materials Science Poland

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2017

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Vol. 35, No. 1

239--245

EN

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 (<1) in coherence with a high dielectric constant ε are promising for the creation of quantum batteries and capacitors.

2

Fe2+- and Er2+-intercalative modification of porous and electron structure of activated carbon and its influence on supercapacitor parameters

Venhryn B.Ya., Grygorchak I.I., Kulyk Yu.O., Mudry S.I., Strelchuk V V, Budzulyak S I, Dovbeshko G I, Fesenko O M

Materials Science Poland

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2014

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Vol. 32, No. 2

272--280

EN

An influence of both porous and electron structure on the processes in an electric double layer (EDL) determining the main working parameters of carbon-based supercapacitors has been studied in order to improve them. The investigations involved impedance spectroscopy, X-ray small angle scattering, confocal micro-Raman spectroscopy, infra-red and M¨ossbauer spectroscopy. Fe2+- and Er2+-intercallative modifications of nanoporous carbon were performed. It was found that the modification process characteristics correlated with the structure parameters of the EDL.

3

Improvement of supercapacitor parameters by nickel ion intercalation into activated carbon

Venhryn B. Y., Grygorchak I. I., Kulyk Y. O., Mudry S. I.

Materials Science Poland

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2013

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Vol. 31, No. 1

126-132

EN

The relation between the porous structure and the electron structure in carbon materials was investigated in order to optimize the effiency of the physical-chemical processes in an electric double layer (EDL) formed at the boundary between the carbon material and the electrolyte (KOH 30 % aqueous solution). In particular, an Ni2+ intercalative modification of nanoporous carbon resulted in more than a triple increase in the specific capacitance and a significant improvement of the charge-discharge kinetics in the EDL.

4

Effect of ultrasonic treatment of activated carbon on capacitive and pseudocapacitive energy storage in electrochemical supercapacitors

Venhryn B. Y., Grygorchak I.I., Stotsko Z. A., Bakhmatyuk B.P., Mudry S.I., Kulyk Yu.O.

Journal of Achievements in Materials and Manufacturing Engineering

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2013

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Vol. 60, nr 2

59--65

EN

Purpose: Use of ultrasonic radiation for improving the properties of activated carbon was the aim of this paper. Increase of density of states at Fermi level was the main factor, responsible for working characteristics of electrochemical supercapacitors. Design/methodology/approach: Working parameters of supercapacitors on the base of activated carbon have been studied by means of precisional porometry, small angle X-ray scattering, cyclic voltamerometry, electrochemical impedance spectroscopy and computer simulation methods. Findings: The possibility to effect the interface between activated carbon and electrolyte by means of ultrasonic treatment in cavitation and noncavitation regimes is proved. It is shown that ultrasonic treatment in noncavitation regimes causes the significant increase of density of states at Fermi level that results in better farad-volt dependences. Research limitations/implications: This research is a complete and accomplished work. Practical implications: Modification of electric double layer by meanans in ultrasonic treatment, proposed in this work, could be regarded as effective way to obtaine the advanced electrode materials in devices of energy generation and storage. Originality/value: This work is important for physics, material science and chemistry because it is related with new possibilities to change the mobility of charge carries in electric double layer by means of ultrasonic irradiation.

5

Hyper capacity of MCM-41 supramoleculer structure in the radiofrequency range

Grygorchak I. I., Vojtovych S. A., Stotsko Z. A., Seredyuk B. A., Tovstyuk N. K.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 49, nr 2

200--203

EN

Purpose: of this paper was: 1) to synthesize supramolecular MCM-41 structure (p-cyanogen phenyl ether of n-heptyl benzoic acid - 40%)>> with inserted guested nematic and 2) to study its dielectric properties. Design/methodology/approach: Supramolecular MCM-41 structure has been synthesized by vacuum encapsulated method at room temperature. Dielectric properties have been studied by impedance spectroscopy method in the frequency range 10-3-106 Hz by “AUTOLAB” complex of “ECO CHEMIE” (Holland), supported by computer programs FRA-2 and GPES. Findings: We have found a tremendous increase of the permittivity and a low value of the tangent of angle of electric losses, as well as the appearance of low frequency inductive response. Practical implications: Super high capacitors of radio range and time-delay lines allow to use them in a direct incorporation into nanoelectronics devices as a new class of super high capacitors and nanostructured time-delay lines. Originality/value: First time we have received: 1) supramolecular structure of the configuration of molecular-lattice nonorganic matrix with a non nematic substrate, 2) significant inductive response in such structures.

6

Porous structure of carbon-based materials studied by means of X-ray small angle scattering method

Venhryn B.Ya., Grygorchak I.I., Kulyk Yu.O., Mudry S.I., Shvets R.Ya.

Optica Applicata

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2008

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Vol. 38, nr 1

119-125

EN

The porous structure of carbon-graphite materials: styrene-divinylbenzene copolymer (SBC) and fruit stones (FS) has been studied by means of X-ray small angle scattering method. The angular dependences of scattered intensities have been obtained and analyzed by means of the Guinier method. The main parameters of porous structure have been determined (inertia radius, pore size distribution functions, specific surface areas).