68 results on '"Alexander G. Medvedev"'
Search Results
2. Novel peroxosolvates of tetraalkylammonium halides: the first case of layers containing hydrogen-bonded peroxide molecules
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Churakov Andrei, Petr V. Prikhodchenko, Mger A. Navasardyan, Alexander G. Medvedev, and Stanislav I. Bezzubov
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chemistry.chemical_compound ,Hydrogen ,Chemistry ,Polymer chemistry ,Molecule ,chemistry.chemical_element ,Halide ,General Materials Science ,General Chemistry ,Condensed Matter Physics ,Hydrogen peroxide ,Peroxide - Abstract
Novel peroxosolvates of tetraalkylammonium halides Et4N+Cl–•2(H2O2) (1), Et4N+Br–•2(H2O2) (2), Me3(ClCH2CH2)N+Cl–•H2O2 (3) and Me3PhN+Cl–•H2O2 (4) were prepared from concentrated hydrogen peroxide and the corresponding structures were determined by X-ray crystallography. Structures 1 and 2 are formed by globose Et4N+ cations and are the first examples of layers containing H-bonded peroxide molecules. By contrast, 3 and 4 are formed by sufficiently aspherical Me3(ClCH2CH2)N+ and Me3PhN+ units and contain infinitely long hydrogen-bonded peroxide-halide chains.
- Published
- 2022
3. Sodium and Potassium tert-Butyl Peroxide Hydrates: Crystal Structure and Properties
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Petr V. Prikhodchenko, M. Yu. Sharipov, Dmitry A. Grishanov, Alexander G. Medvedev, Alexey A. Mikhaylov, and A. V. Churakov
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chemistry.chemical_classification ,Chemistry ,General Chemical Engineering ,Potassium ,Infrared spectroscopy ,chemistry.chemical_element ,General Chemistry ,Crystal structure ,Alkali metal ,Peroxide ,Thermogravimetry ,chemistry.chemical_compound ,Crystallography ,Hydrocarbon ,Molecule - Abstract
Abstract Sodium and potassium tert-butyl peroxide hydrates 2Na+·2C4H9$${\text{O}}_{2}^{ - }$$·7H2O (I) and 2K+· 2C4H9$${\text{O}}_{2}^{ - }$$·4H2O (II) were prepared. According to X-ray diffraction data (CIF files CCDC no. 2081025 (I) and no. 2081024 (II)), the compounds are coordination polymers in which alkali metal atoms have C.N.(Na) of 6 or C.N.(K) of 6 and 8. The crystal packings comprise layers with clearly defined hydrophobic surfaces consisting of hydrocarbon groups and hydrophilic inner areas including water molecules, alkali metal cations, and peroxy groups of the tert-butyl peroxide anions. Compounds were characterized by vibrational spectroscopy, 1H, 13C NMR spectroscopy, thermogravimetry, and differential scanning calorimetry.
- Published
- 2021
4. Synthesis and crystal structure of triphenyltin and lead complexes with organic peroxides
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Alexander G. Medvedev, Mikhail Yu. Sharipov, Dmitry A. Grishanov, Artur V. Eshtukov, Andrei V. Churakov, Ivan A. Buldashov, Pavel A. Egorov, Ovadia Lev, and Petr V. Prikhodchenko
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General Chemistry - Published
- 2022
5. Highly soluble germanium dioxide as a new source of germanium for derivatization with organic compounds
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Artem V. Kansuzyan, Sofia D. Farafonova, Evgeniya A. Saverina, Irina V. Krylova, Victoriya A. Balycheva, Anna Ya. Akyeva, Alexander G. Medvedev, Elena N. Nikolaevskaya, Mikhail P. Egorov, Petr V. Prikhodchenko, and Mikhail A. Syroeshkin
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General Chemistry - Published
- 2022
6. Improved H2S sensitivity of nanosized BaSnO3 obtained by hydrogen peroxide assisted sol-gel processing
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Artem Marikutsa, Andrey A. Dobrovolskii, Marina N. Rumyantseva, Alexey A. Mikhaylov, Alexander G. Medvedev, Ovadia Lev, and Petr V. Prikhodchenko
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History ,Polymers and Plastics ,Mechanics of Materials ,Mechanical Engineering ,Materials Chemistry ,Metals and Alloys ,Business and International Management ,Industrial and Manufacturing Engineering - Published
- 2023
7. Hydrogen peroxide sol–gel coating of microencapsulated phase change materials by metal oxides
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Petr V. Prikhodchenko, Zhichuan J. Xu, Sergey Sladkevich, Ovadia Lev, Sigalit Meker, Konstantin A. Sakharov, Alexey A. Mikhaylov, Dmitry A. Grishanov, and Alexander G. Medvedev
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Materials science ,Oxide ,02 engineering and technology ,engineering.material ,010402 general chemistry ,01 natural sciences ,law.invention ,Biomaterials ,Metal ,chemistry.chemical_compound ,Coating ,law ,Materials Chemistry ,Hydrogen peroxide ,Sodium sulfite ,Aqueous solution ,Graphene ,General Chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Tin oxide ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,chemistry ,Chemical engineering ,visual_art ,Ceramics and Composites ,visual_art.visual_art_medium ,engineering ,0210 nano-technology - Abstract
Hydrogen peroxide assisted sol–gel coating of core-shell microcapsules of phase change materials (PCMs) is reported. A doubly coated paraffin core with an inner poly(melamine-formaldehyde) shell and an outer coating of peroxostannate, peroxoantimonate, their mixture or the respective metal oxides are reported. Triple coating of the paraffin core with a poly(melamine-formaldehyde) inner shell, tin oxide middle layer and graphene oxide outer coating is also achieved by hydrogen peroxide sol–gel processing. The latent heats of the microencapsulated PCMs ranged between 122 and 192 J g−1. The sol–gel process involves stabilization of the peroxostannate or peroxoantimonate sol in basic aqueous hydrogen peroxide and subsequent destabilization and deposition of the sol by addition of an antisolvent. Transformation to the metal oxide coating is conducted by chemical reduction with sodium sulfite or by mild heat treatment without leakage of the paraffin core.
- Published
- 2020
8. Enhanced Thermal Buffering of Phase Change Materials by the Intramicrocapsule Sub per Mille CNT Dopant
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Sergey Sladkevich, Alexey A. Mikhaylov, Vladimir Kulish, Vitaly A. Nikolaev, Ovadia Lev, Alexander G. Medvedev, Jenny Gun, Konstantin A. Sakharov, Petr V. Prikhodchenko, and Zhichuan J. Xu
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Materials science ,Gypsum ,Chemical substance ,Dopant ,020209 energy ,02 engineering and technology ,Carbon nanotube ,engineering.material ,021001 nanoscience & nanotechnology ,Phase-change material ,law.invention ,Chemical engineering ,Magazine ,law ,Thermal ,0202 electrical engineering, electronic engineering, information engineering ,engineering ,General Materials Science ,0210 nano-technology ,Science, technology and society - Abstract
Microencapsulation of a carbon nanotube (CNT)-loaded paraffin phase change material, PCM in a poly(melamine-formaldehyde) shell, and the respective CNT-PCM gypsum composites is explored. Although a very low level (0.001-0.1 wt %) of intramicrocapsule loading of CNT dopant does not change the thermal conductivity of the solid, it increases the measured effusivity and thermal buffering performance during phase transition. The observed effusivity of 0.05 wt % CNT-doped PCM reaches 4000 W s
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- 2020
9. Green Synthesis of a Nanocrystalline Tin Disulfide-Reduced Graphene Oxide Anode from Ammonium Peroxostannate: a Highly Stable Sodium-Ion Battery Anode
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Ovadia Lev, Eldho Edison, Jenny Gun, Dmitry A. Grishanov, Sergey Sladkevich, Alexey A. Mikhaylov, Alexander G. Medvedev, Madhavi Srinivasan, and Petr V. Prikhodchenko
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Battery (electricity) ,Materials science ,Renewable Energy, Sustainability and the Environment ,Graphene ,General Chemical Engineering ,Oxide ,chemistry.chemical_element ,Sodium-ion battery ,02 engineering and technology ,General Chemistry ,Thermal treatment ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,0104 chemical sciences ,law.invention ,Anode ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Environmental Chemistry ,0210 nano-technology ,Tin ,Wet chemistry - Abstract
We introduce a green synthesis approach for high-performance sodium-ion battery anodes that does not involve hydrothermal treatment or excessive energy use. Wet chemistry involving ammonium peroxostannate intermediate coating of reduced graphene oxide can be done at low temperature without excessive use of solvents. The process is practically waste-free and does not involve acid waste. Thermal treatment is required only for the solid material. The electrode exhibited very high stability and the charging capacity was reduced from 320 to 310 mA h g–1 after 2000 cycles at 3 A g–1. Moreover, the synthesis protocol demonstrated here is highly versatile with different, alternative pathways that provide many degrees of freedom in the process sheet design and in material composition.
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- 2020
10. PRODUCTION AND TECHNOLOGICAL PROBLEMS OF SMALL LIVESTOCK FARMS
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Oksana V. Kovrigo, Alexander G. Medvedev, Eteri P. Kvachantiradze, and BLSlawfirm
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Agricultural science ,business.industry ,Production (economics) ,Livestock ,Business - Published
- 2020
11. Hydroperoxo double hydrogen bonding: stabilization of hydroperoxo complexes exemplified by triphenylsilicon and triphenylgermanium hydroperoxides
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Andrei V. Churakov, Ovadia Lev, Petr V. Prikhodchenko, Alexey A. Mikhaylov, Dmitry A. Grishanov, and Alexander G. Medvedev
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Hydrogen ,Hydrogen bond ,Ligand ,Chemistry ,chemistry.chemical_element ,General Chemistry ,Condensed Matter Physics ,Acceptor ,Crystallography ,Main group element ,Moiety ,General Materials Science ,Reactivity (chemistry) ,Isostructural - Abstract
Triphenyl silicon hydroperoxide and its isostructural germanium complex were characterized by single crystal X-ray analysis revealing H-bonding of two triphenylhydroperoxocomplexes, with each hydroperoxo ligand acting as a hydrogen donor and a hydrogen acceptor. Only two other structures with localized protons of hydroperoxo complexes' main group elements (boron and tin) are known (compared to 130 p-block element peroxo compounds) and both exhibit the same hydroperoxo double hydrogen bonding motif. The reaction of the hydroperoxo complexes with triphenylgermanium chloride to give the dinuclear peroxobridged germanium complex demonstrates the higher reactivity of the hydroperoxo moieties compared to the peroxo moiety. DFT calculations provide an estimate of the hydroperoxo double hydrogen bond energies: 62.8 and 63.6 kJ mol−1 for triphenyl silicon, 63.6 and 65 kJ mol−1 for the germanium complex.
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- 2020
12. Probing electrochemical reactivity in an Sb2S3-containing potassium-ion battery anode: observation of an increased capacity
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Alexey M. Glushenkov, Ying Chen, Dmitri Golberg, V. Lakshmi, Alexander G. Medvedev, Ovadia Lev, Alexey A. Mikhaylov, Pavel Cizek, Mokhlesur Rahman, Chao Zhang, Petr V. Prikhodchenko, and Thrinathreddy Ramireddy
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Battery (electricity) ,Materials science ,Renewable Energy, Sustainability and the Environment ,Graphene ,Oxide ,Potassium-ion battery ,02 engineering and technology ,General Chemistry ,Electrolyte ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Anode ,law.invention ,chemistry.chemical_compound ,Chemical engineering ,chemistry ,law ,Electrode ,General Materials Science ,0210 nano-technology - Abstract
Potassium-ion batteries are attracting considerable attention as a viable type of high voltage battery. Among available anode materials, composites containing Sb2S3are some of the most interesting high capacity candidates. A nanostructured Sb2S3-reduced graphene oxide composite anode material is evaluated in this study and compared with a structurally similar SnS2-reduced graphene oxide material reported previously by this team. The behaviour of the Sb2S3-based electrodes is assessed in both 1 M KPF6in ethylene carbonate-diethyl carbonate and 1 M KPF6in 1,2-dimethoxyethane electrolytes. Depotassiation capacities in excess of 650 mA h g−1are recorded for the composite electrodes, superior not only to SnS2-based electrodes but also to all previously reported Sb2S3-containing electrode materials for potassium-ion batteries. In order to establish insights into the reaction mechanism of the Sb2S3phase with potassium, post-cycling X-ray diffraction andin situtransmission electron microscopy are utilised. The recorded data suggest the presence of antimony alloys and potassium polysulphides as reaction products and intermediates; a possible conversion-alloying reaction mechanism is discussed. The results indicate that a capacity higher than previously believed is achievable in the Sb2S3active component of potassium-ion battery electrodes.
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- 2020
13. Stabilization of hydrogen peroxide by hydrogen bonding in the crystal structure of 2-aminobenzimidazole perhydrate
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Petr V. Prikhodchenko, Ovadia Lev, Alexander G. Medvedev, Mikhail V. Vener, Dmitry A. Grishanov, Alexey A. Mikhaylov, Mger A. Navasardyan, Andrei V. Churakov, and Tatiana A. Tripol’skaya
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Proton ,Chemistry ,Hydrogen bond ,General Chemistry ,Crystal structure ,Condensed Matter Physics ,Adduct ,Crystal ,chemistry.chemical_compound ,Physical chemistry ,Molecule ,General Materials Science ,Hydrogen peroxide ,Single crystal - Abstract
2-Aminobenzimidazole hemiperoxosolvate 2(C7H7N3)·H2O2 was synthesized and studied by single crystal X-ray analysis and periodic (solid-state) DFT calculations. The obtained compound, after urea and melamine peroxosolvates, is the third example of an H2O2 crystalline adduct stabilized with the maximum possible number of hydrogen bonds formed by one hydrogen peroxide molecule – 2 H-bonds as proton donors and 4 as acceptors. Due to the small size of the hydrogen peroxide molecule, its hydrogen bonding energy contributes the maximal impact and determines the relative value of the hydrogen bonding energy of the peroxosolvate crystal and can be suggested as an energetic criterion of perhydrate stability. The total energy of the 6 hydrogen bonds formed by one hydrogen peroxide molecule in all three compounds (∼140–∼170 kJ mol−1) was calculated and compared to the corresponding values for crystalline hydrogen peroxide and L-serine peroxosolvate. The total energy of the 4 hydrogen bonds of hydrogen peroxide molecule in crystalline H2O2 and L-serine peroxosolvate (150 and 113 kJ mol−1, respectively) was evaluated by solid-state DFT calculations.
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- 2020
14. Comparison of Proton Acceptor and Proton Donor Properties of H
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Mikhail V, Vener, Andrei V, Churakov, Alexander P, Voronin, Olga D, Parashchuk, Sergei V, Artobolevskii, Oleg A, Alatortsev, Denis E, Makhrov, Alexander G, Medvedev, and Aleksander, Filarowski
- Abstract
Two new peroxosolvates of drug-like compounds were synthesized and studied by a combination of X-ray crystallographic, Raman spectroscopic methods, and periodic DFT computations. The enthalpies of H-bonds formed by hydrogen peroxide (H
- Published
- 2021
15. Speciation of Tellurium(VI) in Aqueous Solutions: Identification of Trinuclear Tellurates by 17O, 123Te, and 125Te NMR Spectroscopy
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Alexander G. Medvedev, Oleg Yu. Savelyev, Dmitry P. Krut’ko, Alexey A. Mikhaylov, Ovadia Lev, and Petr V. Prikhodchenko
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Chemistry (miscellaneous) ,tellurates ,NMR spectroscopy ,trinuclear tellurate ,spin-spin coupling ,DFT computations ,single-crystal X-ray diffraction ,Organic Chemistry ,Drug Discovery ,Molecular Medicine ,Pharmaceutical Science ,Physical and Theoretical Chemistry ,Analytical Chemistry - Abstract
Tellurates have attracted the attention of researchers over the past decade due to their properties and as less toxic forms of tellurium derivatives. However, the speciation of Te(VI) in aqueous solutions has not been comprehensively studied. We present a study of the equilibrium speciation of tellurates in aqueous solutions at a wide pH range, 2.5–15 by 17O, 123Te, and 125Te NMR spectroscopy. The coexistence of monomeric, dimeric, and trimeric oxidotellurate species in chemical equilibrium at a wide pH range has been shown. NMR spectroscopy, DFT computations, and single-crystal X-ray diffraction studies confirmed the formation and coexistence of trimeric tellurate anions with linear and triangular structures. Two cesium tellurates, Cs2[Te4O8(OH)10] and Cs2[Te2O4(OH)6], were isolated from the solution at pH 5.5 and 9.2, respectively, and studied by single-crystal X-ray diffractometry, revealing dimeric and tetrameric tellurate anions in corresponding crystal structures.
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- 2022
16. Unusual Stabilization of Zinc Peroxide by Manganese Oxide: Mechanistic Understanding by Temperature-Dependent EPR Studies
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Alexander I. Shames, Alexey A. Mikhaylov, Petr V. Prikhodchenko, Ovadia Lev, Jenny Gun, and Alexander G. Medvedev
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Inorganic chemistry ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Nanocrystalline material ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,law.invention ,chemistry.chemical_compound ,Potassium permanganate ,General Energy ,chemistry ,law ,Zinc peroxide ,Physical and Theoretical Chemistry ,0210 nano-technology ,Electron paramagnetic resonance - Abstract
Nanocrystalline zinc peroxide is passivated against further oxidation by the addition of minute, substoichiometric amounts of potassium permanganate, which also endows it with increased thermal sta...
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- 2019
17. Brush like polyaniline on vanadium oxide decorated reduced graphene oxide: Efficient electrode materials for supercapacitor
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Ovadia Lev, Alexander G. Medvedev, Sudip Kumar Batabyal, M. Sathish Kumar, K. Yamini Yasoda, Petr V. Prikhodchenko, and Alexey A. Mikhaylov
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Conductive polymer ,Supercapacitor ,Materials science ,Renewable Energy, Sustainability and the Environment ,Graphene ,020209 energy ,Oxide ,Energy Engineering and Power Technology ,Vanadium ,chemistry.chemical_element ,02 engineering and technology ,021001 nanoscience & nanotechnology ,Vanadium oxide ,law.invention ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Electrode ,Polyaniline ,0202 electrical engineering, electronic engineering, information engineering ,Electrical and Electronic Engineering ,0210 nano-technology - Abstract
Vanadium oxides (V3O7) have been used as electrode materials for supercapacitor applications because of its multiple oxidation states. V3O7 nanoparticles were coated on reduced graphene oxide (rGO) from a peroxovanadate-rGO composite by thermal microexplosive decomposition method. These V3O7 decorated rGO were made composite with the flexible multi redox conducting polymer (Polyaniline). The performance of the composite materials as electrode for supercapacitors was analyzed in a 3-electrode cell, obtaining a specific capacitance of about 579 F g−1 at 0.2 A g−1 specific current. Cycling stability is one of the main barriers noticed in V3O7, which limits the practical performance of supercapacitors. This is overcome by modifying V3O7 with rGO and polyaniline composites which produces good electrical contact resulting in higher capacitances and enhanced cycling stability when compared to pristine V3O7. A superior electrochemical performance and ultra-long cyclic stability of 94% over 2500 cycles was obtained through these developed electrodes.
- Published
- 2019
18. Crystalline Ammonium Peroxogermanate as a Waste-Free, Fully Recyclable Versatile Precursor for Germanium Compounds
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Alexey A. Mikhaylov, Petr V. Prikhodchenko, Ovadia Lev, Alexander G. Medvedev, Andrei V. Churakov, and Dmitry A. Grishanov
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Aqueous solution ,010405 organic chemistry ,Inorganic chemistry ,Oxide ,chemistry.chemical_element ,Germanium ,Crystal structure ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Reagent ,Germanate ,Physical and Theoretical Chemistry ,Solubility ,Germanium oxide - Abstract
High, nearly 100%, yield synthesis of ammonium peroxogermanate (APG), (NH4)6[Ge6(μ-OO)6(μ-O)6(OH)6]·6H2O, is presented, and its crystal structure is determined by single crystal X-ray study. It comprises centrosymmetric hexanuclear peroxogermanate anions [Ge6(μ-OO)6(μ-O)6(OH)6]6- with six μ-oxo- and six μ-peroxo groups forming negatively charged layers. The space between these layers is filled by ammonium cations and water molecules, forming a highly stable structure due to hydrogen bonding. Highly soluble macroporous amorphous germanium oxide (HSGO) is then synthesized by mild treatment of APG. The compound forms highly oversaturated metastable germanium oxide solution with a solubility of 100 g/L, over 20 times higher than the solubility of amorphous germanium oxide. HSGO solution is a versatile reagent that can react with basic and acidic reagents to give a diverse range of salts including, e.g., germanium sulfide, germanium hydrophosphate, and potassium germanate. In the absence of acid or base, the aqueous HSGO solution yields hexagonal germanium oxide under ambient conditions.
- Published
- 2019
19. Cyclic dipeptide peroxosolvates: first direct evidence for hydrogen bonding between hydrogen peroxide and a peptide backbone
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Andrei V. Churakov, Petr V. Prikhodchenko, Alexey A. Mikhaylov, Dmitry A. Grishanov, Mikhail V. Vener, Mger A. Navasardyan, Tatiana A. Tripol’skaya, Ovadia Lev, and Alexander G. Medvedev
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Dipeptide ,Chemistry ,Hydrogen bond ,02 engineering and technology ,General Chemistry ,Hydrogen atom ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,01 natural sciences ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Diglycine ,Molecule ,General Materials Science ,0210 nano-technology ,Hydrate ,Hydrogen peroxide ,Protein secondary structure - Abstract
Herein, peroxosolvates of the cyclic dipeptides disarcosine (C6H10N2O2·H2O2), dialanine (C6H10N2O2·2(H2O2)), diglycine (C4H6N2O2·2(H2O2) and C4H6N2O2·1.786(H2O2)·0.214(H2O)) were synthesized and studied by single crystal X-ray analysis and periodic DFT calculations. The hydrogen bonding networks of cyclic diglycine peroxosolvate and isomorphous hydrate were characterized using Bader analysis of periodic electron density and empirical correlations between enthalpy and metric and spectroscopic parameters of the H-bond. The obtained data for the peroxosolvate of cyclic dipeptides provided a molecular-level insight into the non-redox interaction of hydrogen peroxide with the peptide backbone in aqueous systems. In all structures, H2O2 acts as a proton donor in two hydrogen bonds. The carbonyl oxygen atom of the peptide (–CO–NH–) forms a relatively stronger hydrogen bond with the hydrogen peroxide molecule (32–34 kJ mol−1) as compared to that with water in the isomorphous hydrate of cyclic diglycine (26–28 kJ mol−1). The hydrogen atom of the peptide group (–CO–NH–) can form a moderate H-bond with hydrogen peroxide (25 kJ mol−1). The total hydrogen bonding energy of the peroxosolvate is higher than that of the corresponding hydrate (91 vs. 82 kJ mol−1). The stronger hydrogen bonding in peroxosolvates as compared to that in the hydrate and the fact that the intermolecular H-bonds C(O)NH⋯OCNH between cyclic dipeptides are not found in peroxosolvates, despite being prevalent in the structure of nonsolvated dipeptides, imply that hydrogen peroxide can interfere with the secondary structure of proteins via a mechanism that can lead to reversible inhibition or signaling in living systems.
- Published
- 2019
20. Green synthesis of zinc sulfide-reduced graphene oxide composite and its application in sodium-ion batteries
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Alexey A. Mikhaylov, Alexander G. Medvedev, Ivan A. Buldashov, Timur M. Fazliev, Elena A. Mel’nik, Tatiana A. Tripol’skaya, Sergey Sladkevich, Vitaly A. Nikolaev, Ovadia Lev, and Petr V. Prikhodchenko
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Mechanics of Materials ,Mechanical Engineering ,Materials Chemistry ,Metals and Alloys - Published
- 2022
21. Fast Quantum Approach for Evaluating the Energy of Non-Covalent Interactions in Molecular Crystals: The Case Study of Intermolecular H-Bonds in Crystalline Peroxosolvates
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Alexander G. Medvedev, Andrei V. Churakov, Mger A. Navasardyan, Petr V. Prikhodchenko, Ovadia Lev, and Mikhail V. Vener
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Chemistry (miscellaneous) ,peroxosolvates ,macrocyclic ether ,amino acid ,periodic DFT computations ,bifurcated H-bonds ,multicomponent crystals ,B3LYP vs. PBE-D3 ,Organic Chemistry ,Drug Discovery ,Thermodynamics ,Molecular Medicine ,Pharmaceutical Science ,Hydrogen Bonding ,Physical and Theoretical Chemistry ,Analytical Chemistry - Abstract
Energy/enthalpy of intermolecular hydrogen bonds (H-bonds) in crystals have been calculated in many papers. Most of the theoretical works used non-periodic models. Their applicability for describing intermolecular H-bonds in solids is not obvious since the crystal environment can strongly change H-bond geometry and energy in comparison with non-periodic models. Periodic DFT computations provide a reasonable description of a number of relevant properties of molecular crystals. However, these methods are quite cumbersome and time-consuming compared to non-periodic calculations. Here, we present a fast quantum approach for estimating the energy/enthalpy of intermolecular H-bonds in crystals. It has been tested on a family of crystalline peroxosolvates in which the H∙∙∙O bond set fills evenly (i.e., without significant gaps) the range of H∙∙∙O distances from ~1.5 to ~2.1 Å typical for strong, moderate, and weak H-bonds. Four of these two-component crystals (peroxosolvates of macrocyclic ethers and creatine) were obtained and structurally characterized for the first time. A critical comparison of the approaches for estimating the energy of intermolecular H-bonds in organic crystals is carried out, and various sources of errors are clarified.
- Published
- 2022
22. Identification of Barium Hydroxo-Hydroperoxostannate Precursor for Low-Temperature Formation of Perovskite Barium Stannate
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Dmitry A. Grishanov, Alexander G. Medvedev, Alexey A. Mikhaylov, E. A. Mel’nik, Alexander I. Shames, Andrey B. Ilyukhin, Andrei V. Churakov, Tatiana A. Tripol’skaya, Petr V. Prikhodchenko, and Ovadia Lev
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Inorganic Chemistry ,Barium stannate ,Strontium ,chemistry.chemical_compound ,chemistry ,Stannate ,Doping ,Inorganic chemistry ,chemistry.chemical_element ,Barium ,Physical and Theoretical Chemistry ,Colloidal Solution ,Perovskite (structure) - Abstract
A breakthrough "superoxide colloidal solution route" for low-temperature synthesis of barium and strontium stannate perovskites and their doped analogues was recently introduced. The synthesis starts from hydrogen peroxide-rich stannate solutions and yields a so-called "crystalline superoxide molecular cluster" that is converted by low temperature (300 °C) to the respective perovskites. In this paper, the so-called "crystalline superoxide molecular cluster" is identified as a superoxide-free, barium trihydroxo(hydroperoxo)peroxostannate, BaSn(OH)
- Published
- 2020
23. Stabilization of Zinc Peroxide in the Combined Process of Granulation and Encapsulation
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A. V. Zhubrikov, Tatiana A. Tripol’skaya, N. V. Khitrov, E. A. Mel’nik, Alexander G. Medvedev, Petr V. Prikhodchenko, Alexey A. Mikhaylov, I. V. Shabalova, and Vladimir M. Novotortsev
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General Chemical Engineering ,Sodium ,Polyphosphate ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,Combined procedure ,010501 environmental sciences ,engineering.material ,021001 nanoscience & nanotechnology ,01 natural sciences ,Encapsulation (networking) ,chemistry.chemical_compound ,Granulation ,chemistry ,Chemical engineering ,Coating ,engineering ,Zinc peroxide ,0210 nano-technology ,0105 earth and related environmental sciences - Abstract
A combined procedure of zinc peroxide granulation and encapsulation in one technological stage has been developed, which ensures the stabilization of ZnO2 by forming a coating on the surface of the product granules. It is shown that the use of sodium polyphosphate in a combined process of granulation and encapsulation as encapsulating agents with the concentration in the initial solution of 1% allows obtaining a capsular product, which is significantly more resistant to the action of wet carbon dioxide than a nonencapsulated analogue.
- Published
- 2018
24. Graphene oxide supported tin dioxide: synthetic approaches and electrochemical characterization as anodes for lithium- and sodium-ion batteries
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T. A. Tripol´skaya, Alexey A. Mikhaylov, Petr V. Prikhodchenko, and Alexander G. Medvedev
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Graphene ,Tin dioxide ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,engineering.material ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Tin oxide ,01 natural sciences ,0104 chemical sciences ,law.invention ,chemistry.chemical_compound ,chemistry ,Coating ,Chemical engineering ,law ,Mechanochemistry ,engineering ,Lithium ,0210 nano-technology ,Tin - Abstract
The review addresses synthetic approaches to composite materials based on graphene oxide and nano tin dioxide and their electrochemical properties as anodes for lithium- and sodiumion batteries. The introduction of a carbon matrix into the composite material improves the electrochemical characteristics of the anodes. In most methods, the synthesis of graphene oxide–tin dioxide composites is based on the use of tin(II,IV) chlorides as the starting compounds, and the most efficient electrode materials were obtained by the hydrothermal or solvothermal routes. Thermal processing is much more economic than the gas phase deposition protocols but requires heating of a large volume of dilute tin oxide dispersions in an autoclave. Mechanochemistry (ball milling) is also economically unfavorable for the synthesis of composite materials. In addition, large volumes of acidic wastes that should be neutralized and safely discarded are formed when tin chlorides are used. An alternative environmentally friendly technique based on the use of aqueous peroxide solutions can be applied for the production of efficient anode materials based on graphene oxide and tin dioxide. This process does not involve acidic wastes, uses hydrogen peroxide and ethanol as reagents, and accomplishes film deposition (coating) at room temperature. Final thermal treatment is required only for the active material, which minimizes energy expenses and equipment costs.
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- 2018
25. Vanadium Oxide Thin Film Formation on Graphene Oxide by Microexplosive Decomposition of Ammonium Peroxovanadate and Its Application as a Sodium Ion Battery Anode
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Sergey Sladkevich, Dmitry A. Grishanov, Alexander G. Medvedev, Arun Nagasubramanian, Ovadia Lev, Alexey A. Mikhaylov, Madhavi Srinivasan, Petr V. Prikhodchenko, Zhichuan J. Xu, Jenny Gun, Singapore-HUJ Alliance for Research and Enterprise, NEW-CREATE Phase II Campus for Research Excellence and Technological Enterprise, and Energy Research Institute @ NTU (ERI@N)
- Subjects
Materials science ,Oxide ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Vanadium oxide ,law.invention ,chemistry.chemical_compound ,law ,Electrochemistry ,General Materials Science ,Thin film ,Spectroscopy ,Graphene ,Two Dimensional Materials ,Sodium-ion battery ,Oxides ,Surfaces and Interfaces ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Nanocrystalline material ,0104 chemical sciences ,Anode ,Microcrystalline ,chemistry ,Chemical engineering ,Electrical and electronic engineering [Engineering] ,0210 nano-technology - Abstract
Formation of vanadium oxide nanofilm-coated graphene oxide (GO) is achieved by thermally induced explosive disintegration of a microcrystalline ammonium peroxovanadate-GO composite. GO sheets isolate the microcrystalline grains and capture and contain the microexplosion products, resulting in the deposition of the nanoscale products on the GO. Thermal treatment of the supported nanofilm yields a sequence of nanocrystalline phases of vanadium oxide (V3O7, VO2) as a function of temperature. This is the first demonstration of microexplosive disintegration of a crystalline peroxo compound to yield a nanocoating. The large number of recently reported peroxide-rich crystalline materials suggests that the process can be a useful general route for nanofilm formation. The V3O7@GO composite product was tested as a sodium ion battery anode and showed high charge capacity at high rate charge-discharge cycling (150 mAh g-1 at 3000 mA g-1 vs 300 mAh g-1 at 100 mA g-1) due to the nanomorphology of the vanadium oxide. NRF (Natl Research Foundation, S’pore)
- Published
- 2018
26. Synthesis of high volumetric capacity graphene oxide-supported tellurantimony Na- and Li-ion battery anodes by hydrogen peroxide sol gel processing
- Author
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Alexey A. Mikhaylov, Dmitry A. Grishanov, Arun Nagasubramanian, Petr V. Prikhodchenko, Jenny Gun, Alexander G. Medvedev, Srinivasan Madhavi, Ovadia Lev, and Energy Research Institute @ NTU (ERI@N)
- Subjects
Antimony ,Battery (electricity) ,Telluride ,Materials science ,Inorganic chemistry ,Oxide ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,law.invention ,Biomaterials ,chemistry.chemical_compound ,Colloid and Surface Chemistry ,law ,Electrical resistivity and conductivity ,Chemistry [Science] ,Sol-gel ,Graphene ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Anode ,chemistry ,Electrode ,0210 nano-technology ,Current density - Abstract
High-charge-capacity sodium-ion battery anodes made of Sb2Te3@reduced graphene oxide are reported for the first time. Uniform nano-coating of graphene oxide is carried out from common sol of peroxotellurate and peroxoantimonate under room temperature processing. Reduction by hydrazine under glycerol reflux yields Sb2Te3@reduced graphene oxide. The electrodes exhibit exceptionally high volumetric charge capacity, above 2300mAhcm-3 at 100mAg-1 current density, showing very good rate capabilities and retaining 60% of this capacity even at 2000mAg-1. A comparison of sodiation and lithiation shows that lithiation exhibits better volumetric charge capacity, but surprisingly only marginally better relative rate capability retention at 2000mAg-1. Tellurium-based electrodes are attractive due to the high volumetric charge capacity of Te, its very high electric conductivity, and the low relative expansion upon lithiation/sodiation.
- Published
- 2018
27. A composite based on sodium germanate and reduced graphene oxide: Synthesis from peroxogermanate and application as anode material for lithium ion batteries
- Author
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Ovadia Lev, Dmitry A. Grishanov, Petr V. Prikhodchenko, Tatiana A. Tripol’skaya, Alexey A. Mikhaylov, E. A. Mel’nik, and Alexander G. Medvedev
- Subjects
Materials science ,Graphene ,Materials Science (miscellaneous) ,Sodium ,Oxide ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,0104 chemical sciences ,Anode ,law.invention ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,law ,Lithium ,Physical and Theoretical Chemistry ,Thin film ,0210 nano-technology ,Sodium germanate - Abstract
A composite based on sodium germanate and reduced graphene oxide was obtained for the first time by precipitating the initial peroxogermanate on a graphene oxide followed by heat treatment in vacuum. According to powder X-ray diffraction, sodium germanate crystallizes during the heat treatment in vacuum at 500°C. Scanning transmission electron microscopy examination showed that sodium peroxogermanate nanoparticles form a thin film on the surface of graphene oxide flakes. The electrochemical characteristics of composites obtained with different heat treatment conditions were studied as the anodes of lithium ion batteries.
- Published
- 2017
28. Graphene Oxide-Supported β-Tin Telluride Composite for Sodium- and Lithium-Ion Battery Anodes
- Author
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Alexander G. Medvedev, Petr V. Prikhodchenko, Ovadia Lev, Zhichuan J. Xu, Jenny Gun, Alexey A. Mikhaylov, Madhavi Srinivasan, Dmitry A. Grishanov, Arun Nagasubramanian, and Energy Research Institute @ NTU (ERI@N)
- Subjects
Materials science ,Graphene ,Sodium ,Inorganic chemistry ,Composite number ,Oxide ,chemistry.chemical_element ,Hydrogen Peroxide ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Lithium-ion battery ,0104 chemical sciences ,law.invention ,Anode ,Tin telluride ,chemistry.chemical_compound ,General Energy ,chemistry ,law ,Chemistry [Science] ,Graphene Oxide ,0210 nano-technology ,Hydrogen peroxide - Abstract
High‐charge‐capacity sodium‐ and lithium‐ion battery anodes based on tin telluride are reported for the first time. Graphene oxide/cubic β‐SnTe electrodes exhibit exceptionally high reversible volumetric charge capacities above 3000 and 1300 mAh cm−3 at 100 mA g−1 charging rate for lithium and sodium ion batteries, respectively, and they show very good rate capabilities retaining 68 and 60 % of the respective capacities even at 2000 mA g−1 charging rate. The reversible charge capacity for lithiation is approximately equal to the theoretical value of the active material. The superior electrode performance is attributed to the high conductivity of tellurium, the mechanical buffering of volume changes by the large row‐V host elements, the elasticity of the reduced graphene oxide support, and the very low specific equivalent volumes involved in sodiation and lithiation of SnTe. NRF (Natl Research Foundation, S’pore)
- Published
- 2017
29. On the stability of Al13 Keggin cation in aqueous hydrogen peroxide solutions
- Author
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Alexander G. Medvedev, L. V. Kolyadintseva, Alexey A. Mikhaylov, Tatiana A. Tripol’skaya, Petr V. Prikhodchenko, Andrei V. Churakov, and E. A. Mel’nik
- Subjects
Aqueous solution ,010405 organic chemistry ,Chemistry ,Materials Science (miscellaneous) ,Inorganic chemistry ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Chloride ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Aluminium ,Sodium sulfate ,medicine ,Molecule ,Physical and Theoretical Chemistry ,Sulfate ,Hydrogen peroxide ,medicine.drug - Abstract
We report the first attempt to study the behavior of the [AlO4Al12(OH)25(H2O)11]6+ (Al13) Keggin cation (KC) in water–peroxide solutions. Addition of hydrogen peroxide into an aqueous solution containing the Al13 KC reduces pH due to the acidity of hydrogen peroxide. According to the 27Al NMR studies of water–peroxide solutions prepared just before the NMR experiment, with their pH adjusted to the initial value of 5.5 with aqueous NaOH, the Al13 KC concentration decreases immediately once hydrogen peroxide is added to the initial system. Addition of 18.2 wt % hydrogen peroxide to the initial 0.88 mM Al13 solution gives rise to a fourfold decline in Al13 polyoxo cation concentration to 0.22 mM. Then, the KC concentration in the test system remains unchanged for 1 week. Large hydrogen peroxide amounts (27.9 wt % or higher) added to the initial system almost completely degrade the KC. Sodium sulfate added to the initial water–peroxide solution of Al13 chloride where the hydrogen peroxide concentration is 5.5 wt % precipitates the earlier described Al13 sulfate [AlO4Al12(OH)25(H2O)11](SO4)3 · 16H2O, where the aluminum polyoxo cation does not contain coordinated hydrogen peroxide molecules, peroxo or hydroperoxo groups as shown by X-ray diffraction.
- Published
- 2017
30. Crystal structure of (Z)-N-benzylidene-1-phenylmethanamine oxide hydrogen peroxide monosolvate
- Author
-
Petr V. Prikhodchenko, Alexander G. Medvedev, Andrei V. Churakov, and Alexey A. Mikhaylov
- Subjects
crystal structure ,Oxide ,Crystal structure ,hydrogen-bond motif ,Dihedral angle ,010402 general chemistry ,Photochemistry ,01 natural sciences ,Peroxide ,Adduct ,Nitrone ,Crystal ,chemistry.chemical_compound ,General Materials Science ,Hydrogen peroxide ,nitrone ,chemistry.chemical_classification ,Crystallography ,010405 organic chemistry ,General Chemistry ,Condensed Matter Physics ,N-oxide ,0104 chemical sciences ,chemistry ,QD901-999 ,peroxosolvate - Abstract
The title adduct, C14H13NO·H2O2, consists of (Z)-N-benzylidene-1-phenylmethanamine oxide and hydrogen peroxide molecules in a 1:1 ratio. The organic coformer adopts a skew geometry with an inter-aryl-ring dihedral angle of 81.9 (2)°. In the crystal, the organic and peroxide molecules are linked through both peroxide O—H donor groups to oxide O-atom acceptors, giving one-dimensional chains extending along thebaxis. Present also are weak intermolecular C—H...O hydrogen-bonding interactions.
- Published
- 2017
31. Hydrogen Peroxide Insular Dodecameric and Pentameric Clusters in Peroxosolvate Structures
- Author
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Dmitry A. Grishanov, Mger A. Navasardyan, Alexander G. Medvedev, Ovadia Lev, Petr V. Prikhodchenko, and Andrei V. Churakov
- Subjects
chemistry.chemical_classification ,010405 organic chemistry ,Stereochemistry ,Hydrogen bond ,Supramolecular chemistry ,Peptide ,General Medicine ,General Chemistry ,Crystal structure ,010402 general chemistry ,01 natural sciences ,Catalysis ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Cluster (physics) ,Molecule ,Homoleptic ,Hydrogen peroxide - Abstract
Peroxosolvates of 2-aminonicotinic acid (I) and lidocaine N-oxide (II) including the largest insular hydrogen peroxide clusters were isolated and their crystal structures were determined by single-crystal X-ray diffraction. An unprecedented dodecameric hydrogen peroxide insular cluster was found in I. An unusual cross-like pentameric cluster was observed in the structure of II. The topology of the (H2 O2 )12 assembly was never observed for small-molecule clusters. In I and II new double and triple cross-orientational disorders of H2 O2 were found. Cluster II is the first example of a peroxosolvate crystal structure containing H2 O2 molecules with a homoleptic hydrogen peroxide environment. In II, a hydrogen bond between an H2 O2 molecule and a peptide group -CONH⋅⋅⋅O2 H2 was observed for the first time.
- Published
- 2017
32. Development of combined granulation and encapsulation process in production of sodium percarbonate
- Author
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Tatiana A. Tripol’skaya, Alexander G. Medvedev, I. V. Shabalova, A. V. Zhubrikov, Vladimir M. Novotortsev, Fedor V. Grechnikov, Petr V. Prikhodchenko, E. A. Mel’nik, A. A. Mikhailov, and N. V. Khitrov
- Subjects
animal structures ,Chromatography ,General Chemical Engineering ,Polyphosphate ,Sodium ,fungi ,chemistry.chemical_element ,General Chemistry ,010501 environmental sciences ,Sodium percarbonate ,engineering.material ,010402 general chemistry ,Oxyethylidenediphosphonic acid ,01 natural sciences ,0104 chemical sciences ,Encapsulation (networking) ,chemistry.chemical_compound ,Granulation ,chemistry ,Coating ,Chemical engineering ,engineering ,Solubility ,0105 earth and related environmental sciences - Abstract
A combined granulation and encapsulation procedure in the production of sodium percarbonate (SPC) has been developed that enables the stabilization of SPC to form a coating on the surface of product granules in one technological stage. The separation of the granulating and encapsulating agents during the drying process and formation of an encapsulating coating are performed due to large differences in the solubility of the components of initial solution. Sodium polyphosphate or oxyethylidenediphosphonic acid used as encapsulating agents with an initial solution concentration (1%) in the combined granulation and encapsulation process enables the preparation of encapsulated SPC, which is significantly more resistant to wet carbon dioxide than unencapsulated product.
- Published
- 2017
33. GeO2 Thin Film Deposition on Graphene Oxide by the Hydrogen Peroxide Route: Evaluation for Lithium-Ion Battery Anode
- Author
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Petr V. Prikhodchenko, Alexey A. Mikhaylov, Dmitry A. Grishanov, Ovadia Lev, Alexander G. Medvedev, Sergey Sladkevich, Jenny Gun, and Denis Y. W. Yu
- Subjects
Materials science ,Graphene ,Inorganic chemistry ,Oxide ,chemistry.chemical_element ,Germanium ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Lithium-ion battery ,0104 chemical sciences ,Anode ,Amorphous solid ,law.invention ,chemistry.chemical_compound ,X-ray photoelectron spectroscopy ,chemistry ,law ,General Materials Science ,Thin film ,0210 nano-technology - Abstract
A peroxogermanate thin film was deposited in high yield at room temperature on graphene oxide (GO) from peroxogermanate sols. The deposition of the peroxo-precursor onto GO and the transformations to amorphous GeO2, crystalline tetragonal GeO2, and then to cubic elemental germanium were followed by electron microscopy, XRD, and XPS. All of these transformations are influenced by the GO support. The initial deposition is explained in view of the sol composition and the presence of GO, and the different thermal transformations are explained by reactions with the graphene support acting as a reducing agent. As a test case, the evaluation of the different materials as lithium ion battery anodes was carried out revealing that the best performance is obtained by amorphous germanium oxide@GO with >1000 mAh g–1 at 250 mA g–1 (between 0 and 2.5 V vs Li/Li+ cathode), despite the fact that the material contained only 51 wt % germanium. This is the first demonstration of the peroxide route to produce peroxogermanate ...
- Published
- 2017
34. H2O2induced formation of graded composition sodium-doped tin dioxide and template-free synthesis of yolk–shell SnO2particles and their sensing application
- Author
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Petr V. Prikhodchenko, Alexander G. Medvedev, Ovadia Lev, D. P. Krut'ko, Victor S. Popov, Artem S. Mokrushin, Tatiana A. Tripol’skaya, and Alexey A. Mikhaylov
- Subjects
Aqueous solution ,Tin dioxide ,Sodium ,Inorganic chemistry ,Nanoparticle ,chemistry.chemical_element ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Sodium stannate ,Tin oxide ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,Dynamic light scattering ,chemistry ,Solubility ,0210 nano-technology - Abstract
Sodium peroxostannate nanoparticles with graded composition were produced from aqueous hydrogen peroxide–sodium hydroxostannate solution. The uniform particles were converted to composition graded sodium stannate by mild thermal treatment for peroxide decomposition and yielded yolk–shell tin dioxide particles by dilute acid treatment. The mechanism of formation of the graded sodium concentration is explained in view of the solubility of peroxostannate in H2O2–H2O solution and based on 119Sn NMR, XRD, dynamic light scattering (DLS) and electron microscopy studies. Initial studies illuminating sensitive hydrogen sensing by yolk–shell tin oxide particles are presented.
- Published
- 2017
35. Nanocrystalline SnS2coated onto reduced graphene oxide: demonstrating the feasibility of a non-graphitic anode with sulfide chemistry for potassium-ion batteries
- Author
-
Alexey M. Glushenkov, Alexander G. Medvedev, Petr V. Prikhodchenko, Ovadia Lev, V. Lakshmi, Alexey A. Mikhaylov, Mokhlesur Rahman, Irin Sultana, and Ying Chen
- Subjects
Sulfide ,Inorganic chemistry ,Oxide ,Nanoparticle ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Catalysis ,law.invention ,chemistry.chemical_compound ,law ,Materials Chemistry ,Graphite ,Graphene oxide paper ,chemistry.chemical_classification ,Chemistry ,Graphene ,Metals and Alloys ,General Chemistry ,021001 nanoscience & nanotechnology ,Nanocrystalline material ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,Anode ,Ceramics and Composites ,0210 nano-technology - Abstract
An anode material incorporating a sulfide is reported. SnS2 nanoparticles anchored onto reduced graphene oxide are produced via a chemical route and demonstrate an impressive capacity of 350 mA h g−1, exceeding the capacity of graphite. These results open the door for a new class of high capacity anode materials (based on sulfide chemistry) for potassium-ion batteries.
- Published
- 2017
36. Peroxosolvates: Formation Criteria, H2O2 Hydrogen Bonding, and Isomorphism with the Corresponding Hydrates
- Author
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Ovadia Lev, Ivan Yu. Chernyshov, Mikhail V. Vener, Alexander G. Medvedev, Petr V. Prikhodchenko, and Andrei V. Churakov
- Subjects
Hydrogen ,010405 organic chemistry ,Stereochemistry ,Hydrogen bond ,chemistry.chemical_element ,Isomorphism (crystallography) ,General Chemistry ,Crystal structure ,010402 general chemistry ,Condensed Matter Physics ,01 natural sciences ,Redox ,0104 chemical sciences ,Crystallography ,chemistry ,Isomorphous substitution ,Molecule ,General Materials Science ,Brønsted–Lowry acid–base theory - Abstract
The Cambridge Structural Database has been used to investigate the detailed environment of H2O2 molecules and hydrogen-bond patterns within “true” peroxosolvates in which the H2O2 molecules do not interact directly with the metal atoms. A study of 65 crystal structures and over 260 hydrogen bonds reveals that H2O2 always forms two H-bonds as proton donors and up to four H-bonds as a proton acceptor, but the latter can be absent altogether. The necessary features of peroxosolvate coformers are clarified. (1) Coformers should not participate in redox reactions with H2O2 and should not catalyze its decomposition. (2) Coformers should be Bronsted bases or exhibit amphoteric properties. The efficiency of the proposed criteria for peroxosolvate formation is illustrated by the synthesis and characterization of several new crystals. Conditions preventing the H2O2/H2O isomorphous substitution are essential for peroxosolvate stability: (1) Every H2O2 in the peroxosolvate has to participate in five or six hydrogen b...
- Published
- 2016
37. Morphology and electrochemical properties of a composite produced by a peroxide method on the basis of tin dioxide and carbon black
- Author
-
Petr V. Prikhodchenko, Tatiana A. Tripol’skaya, Ovadia Lev, E. A. Mel’nik, Alexey A. Mikhaylov, and Alexander G. Medvedev
- Subjects
Materials science ,Tin dioxide ,Materials Science (miscellaneous) ,Inorganic chemistry ,Composite number ,02 engineering and technology ,Carbon black ,engineering.material ,equipment and supplies ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,01 natural sciences ,Peroxide ,0104 chemical sciences ,Anode ,Inorganic Chemistry ,chemistry.chemical_compound ,Coating ,chemistry ,engineering ,Physical and Theoretical Chemistry ,0210 nano-technology ,Electrochemical reduction of carbon dioxide - Abstract
Using peroxostannate as a precursor, a composite material based on tin dioxide and carbon black was obtained, in which tin dioxide forms a coating on the surface of carbon black nanoparticles. The synthesized material was characterized by electron microscopy and X-ray powder diffraction analysis, and also the electrochemical characteristics of this material as an anode material for lithium-ion batteries were studied. The material demonstrates good stability and rate performance, which is indicative of the efficiency of the peroxide method for producing promising inexpensive anode materials based on tin dioxide and carbon black.
- Published
- 2016
38. The Crystal Structure of Guanidinium Sulphate Hemiperoxosolvate
- Author
-
Mger A. Navasardyan, Dmitry A. Grishanov, Petr V. Prikhodchenko, Alexander G. Medvedev, and Andrei V. Churakov
- Subjects
chemistry.chemical_compound ,Crystallography ,Chemistry ,Hydrogen bond ,General Chemical Engineering ,General Chemistry ,Crystal structure ,Hydrogen peroxide - Published
- 2018
39. Study of tin dioxide–sodium stannate composite obtained by decomposition of peroxostannate as a potential anode material for lithium-ion batteries
- Author
-
Tatiana A. Tripol’skaya, E. A. Mel’nik, I. V. Shabalova, Ovadia Lev, Petr V. Prikhodchenko, Alexey A. Mikhaylov, and Alexander G. Medvedev
- Subjects
Materials science ,Stannate ,Tin dioxide ,Materials Science (miscellaneous) ,Inorganic chemistry ,Composite number ,chemistry.chemical_element ,02 engineering and technology ,Thermal treatment ,equipment and supplies ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Electrochemistry ,Sodium stannate ,01 natural sciences ,0104 chemical sciences ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Lithium ,Physical and Theoretical Chemistry ,0210 nano-technology ,Tin - Abstract
A tin dioxide–sodium stannate composite has been obtained by the thermal treatment of sodium peroxostannate nanoparticles at 500°C in air. X-ray powder diffraction study has revealed that the composite includes crystalline phases of cassiterite SnO2, sodium stannate Na2Sn2O5, and sodium hexahydroxostannate Na2Sn(OH)6. Scanning electron microscopy has shown that material morphology does not change considerably as compared with the initial tin peroxo compound. Electrochemical characteristics have been compared for the anodes of lithium-ion batteries based on tin dioxide–sodium stannate composite and anodes based on a material manufactured by the thermal treatment of graphene oxide–tin dioxide–sodium stannate composite at 500°C in air.
- Published
- 2016
40. Biocomposite Based on Reduced Graphene Oxide Film Modified with Phenothiazone and Flavin Adenine Dinucleotide-Dependent Glucose Dehydrogenase for Glucose Sensing and Biofuel Cell Applications
- Author
-
Alexey A. Mikhaylov, Lital Alfonta, Ovadia Lev, Alexander G. Medvedev, Lin Xia, Jenny Gun, and Yehonatan Ravenna
- Subjects
Bioelectric Energy Sources ,Inorganic chemistry ,Oxide ,Biocompatible Materials ,Biosensing Techniques ,02 engineering and technology ,010402 general chemistry ,7. Clean energy ,01 natural sciences ,Redox ,Analytical Chemistry ,law.invention ,chemistry.chemical_compound ,Electron transfer ,Phenothiazines ,law ,Glucose dehydrogenase ,Electrodes ,Flavin adenine dinucleotide ,Graphene ,Glucose 1-Dehydrogenase ,Oxides ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Glucose ,chemistry ,Electrode ,Flavin-Adenine Dinucleotide ,Graphite ,0210 nano-technology ,Oxidation-Reduction ,Biosensor - Abstract
A novel composite material for the encapsulation of redox enzymes was prepared. Reduced graphene oxide film with adsorbed phenothiazone was used as a highly efficient composite for electron transfer between flavin adenine dinucleotide (FAD)-dependent glucose dehydrogenase and electrodes. Measured redox potential for glucose oxidation was lower than 0 V vs Ag/AgCl electrode. The fabricated biosensor showed high sensitivity of 42 mA M(-1) cm(-2), a linear range of glucose detection of 0.5-12 mM, and good reproducibility and stability as well as high selectivity for different interfering compounds. In a semibiofuel cell configuration, the hybrid film generated high power output of 345 μW cm(-2). These results demonstrate a promising potential for this composition in various bioelectronic applications.
- Published
- 2015
41. Potassium, Cesium, and Ammonium Peroxogermanates with Inorganic Hexanuclear Peroxo Bridged Germanium Anion Isolated from Aqueous Solution
- Author
-
Ovadia Lev, Andrei V. Churakov, Tatiana A. Tripol’skaya, Mikhail V. Vener, Alexey A. Mikhaylov, Petr V. Prikhodchenko, Shmuel Cohen, and Alexander G. Medvedev
- Subjects
Aqueous solution ,Chemistry ,Potassium ,Inorganic chemistry ,chemistry.chemical_element ,Crystal structure ,Peroxide ,Inorganic Chemistry ,chemistry.chemical_compound ,Thermal stability ,Chemical stability ,Ammonium ,Physical and Theoretical Chemistry ,Hydrogen peroxide - Abstract
Potassium (K6[Ge6(μ-OO)6(μ-O)6(OH)6]·14H2O, 1), cesium ammonium (Cs4.2(NH4)1.8[Ge6(μ-OO)6(μ-O)6(OH)6]·8H2O, 2), and potassium ammonium (K2.4(NH4)3.6[Ge6(μ-OO)6(μ-O)6(OH)6]·6H2O, 3) peroxogermanates were isolated from 3% hydrogen peroxide aqueous solutions of the corresponding hydroxogermanates and characterized by single crystal and powder X-ray diffraction studies and by Raman spectroscopy and thermal analysis. The crystal structure of all three compounds consists of cations of potassium and/or ammonium and cesium, water molecules, and centrosymmetric hexanuclear peroxogermanate anion [Ge6(μ-OO)6(μ-O)6(OH)6](6-) with six μ-oxo- and six μ-peroxo groups. Peroxogermanates demonstrate relatively high thermal stability: the peroxide remains in the structure even after water release after heating to 100-120 °C. DFT calculations of the peroxogermanate [Ge6(μ-OO)6(μ-O)6(OH)6](6-) anion confirm its higher thermodynamic stability compared to the hydroperoxo- and oxogermanate analogues.
- Published
- 2015
42. The applicability of the dimeric heterosynthon concept to molecules with equivalent binding sites. A DFT study of crystalline urea–H2O2
- Author
-
A. V. Shishkina, Ovadia Lev, Mikhail V. Vener, Petr V. Prikhodchenko, and Alexander G. Medvedev
- Subjects
Solvent ,Crystal ,Crystallography ,Computational chemistry ,Chemistry ,General Chemical Engineering ,Intermolecular force ,Polar ,Molecule ,General Chemistry ,Crystal structure ,Structural motif ,Electronic density - Abstract
The limited applicability of the dimeric heterosynthon concept to a two-component urea–H2O2 crystal is reported. It is due to the absence of the relatively short O–H⋯O bonds, i.e. primary interactions, in the urea–H2O2 1 : 1 complex. The target O–H⋯O bonds do exists in trimeric heterosynthons, i.e. the urea–2(H2O2) and 2(urea)–H2O2 complexes. The mutual orientation of the H2O2 molecules in the gas-phase complexes differs from the one in the crystalline structure due to the existence of additional N–H⋯O bonds which are absent in the crystal. Implicitly accounting for the polar environment does not change the molecule conformations in the considered complexes. It is found that the DFT computations with/without accounting for polar solvent are not sufficient for the deduction of such a heterosynthon. The results of the database analysis should be used for unambiguous identification of the molecules' conformations in the target trimeric heterosynthon. An approach for deducing the trimeric heterosynthon structure for molecules with equivalent binding sites is developed. It includes three steps. (i) Identification of structural motifs formed by the considered molecules in the two-component crystals using database analysis. (ii) Establishing a hierarchy of the intermolecular interactions in the crystals by solid-state DFT followed by Bader analysis of the periodic electronic density. (iii) Evaluation of the structure and relative stability of the trimeric heterosynthons by DFT methods with/without accounting for environmental effects.
- Published
- 2015
43. Graphene oxide supported sodium stannate lithium ion battery anodes by the peroxide route: low temperature and no waste processing
- Author
-
Petr V. Prikhodchenko, Chad W. Mason, Alexey A. Mikhaylov, Srinivasan Madhavi, Jenny Gun, Ovadia Lev, Sudip Kumar Batabyal, Arun Nagasubramanian, Qichun Zhang, and Alexander G. Medvedev
- Subjects
Materials science ,Lithium vanadium phosphate battery ,Renewable Energy, Sustainability and the Environment ,Graphene ,Inorganic chemistry ,Oxide ,General Chemistry ,Thermal treatment ,Sodium stannate ,Lithium-ion battery ,law.invention ,Anode ,chemistry.chemical_compound ,chemistry ,law ,Lithium chloride ,General Materials Science - Abstract
Since there has been a notable improvement in the performance of graphene-supported tin-based lithium ion battery anodes, they have become a viable alternative to state of the art graphite anodes. However, currently these anodes are produced by energy-demanding thermal processes and generate lithium chloride or other wastes. In this research, we demonstrate the formation of efficient and stable lithium ion battery anodes based on sodium stannate-coated reduced graphene oxide. Coating is performed at low temperatures and when a sodium peroxostannate precursor is used, the process can be carried out with zero waste discharge. Thermal treatment is required only for the solid material. The anode exhibited a charge capacity of 610 mA h g−1 after 140 cycles at 100 mA g−1. This is the first characterization of a sodium stannate-based anode for LIBs.
- Published
- 2015
44. Crystal structure of ammonium succinate peroxosolvate
- Author
-
A. A. Mikhailov, Petr V. Prikhodchenko, Tatiana A. Tripol’skaya, Alexander G. Medvedev, and Andrei V. Churakov
- Subjects
Hydrogen ,Solid-state physics ,Chemistry ,Hydrogen bond ,Low-barrier hydrogen bond ,chemistry.chemical_element ,Crystal structure ,Acceptor ,Inorganic Chemistry ,Crystallography ,chemistry.chemical_compound ,Materials Chemistry ,Molecule ,Physical and Theoretical Chemistry ,Hydrogen peroxide - Abstract
The crystal structure of previously unknown ammonium succinate peroxosolvate is studied. It is shown that it represents a rare example of the structure where H2O2 molecule forms two donor hydrogen bonds and does participate in any acceptor hydrogen bonds, despite the presence of substantial quantity of nonperoxide active hydrogen atoms.
- Published
- 2014
45. H
- Author
-
Alexey A, Mikhaylov, Alexander G, Medvedev, Tatiana A, Tripol'skaya, Victor S, Popov, Artem S, Mokrushin, Dmitry P, Krut'ko, Petr V, Prikhodchenko, and Ovadia, Lev
- Abstract
Sodium peroxostannate nanoparticles with graded composition were produced from aqueous hydrogen peroxide-sodium hydroxostannate solution. The uniform particles were converted to composition graded sodium stannate by mild thermal treatment for peroxide decomposition and yielded yolk-shell tin dioxide particles by dilute acid treatment. The mechanism of formation of the graded sodium concentration is explained in view of the solubility of peroxostannate in H
- Published
- 2017
46. Crystal structure of (
- Author
-
Andrei V, Churakov, Petr V, Prikhodchenko, Alexander G, Medvedev, and Alexey A, Mikhaylov
- Subjects
nitrone ,crystal structure ,peroxosolvate ,hydrogen-bond motif ,Research Communications ,N-oxide - Abstract
The title structure consists of a (Z)-N-benzylidene-1-phenylmethanamine oxide and a hydrogen peroxide molecule linked through both O—H groups into a one-dimensional chain structure., The title adduct, C14H13NO·H2O2, consists of (Z)-N-benzylidene-1-phenylmethanamine oxide and hydrogen peroxide molecules in a 1:1 ratio. The organic coformer adopts a skew geometry with an inter-aryl-ring dihedral angle of 81.9 (2)°. In the crystal, the organic and peroxide molecules are linked through both peroxide O—H donor groups to oxide O-atom acceptors, giving one-dimensional chains extending along the b axis. Present also are weak intermolecular C—H⋯O hydrogen-bonding interactions.
- Published
- 2017
47. Nanocrystalline SnS
- Author
-
V, Lakshmi, Ying, Chen, Alexey A, Mikhaylov, Alexander G, Medvedev, Irin, Sultana, Md Mokhlesur, Rahman, Ovadia, Lev, Petr V, Prikhodchenko, and Alexey M, Glushenkov
- Abstract
An anode material incorporating a sulfide is reported. SnS
- Published
- 2017
48. GeO
- Author
-
Alexander G, Medvedev, Alexey A, Mikhaylov, Dmitry A, Grishanov, Denis Y W, Yu, Jenny, Gun, Sergey, Sladkevich, Ovadia, Lev, and Petr V, Prikhodchenko
- Abstract
A peroxogermanate thin film was deposited in high yield at room temperature on graphene oxide (GO) from peroxogermanate sols. The deposition of the peroxo-precursor onto GO and the transformations to amorphous GeO
- Published
- 2017
49. Renewable zinc dioxide nanoparticles and coatings
- Author
-
Alexander G. Medvedev, Alexey A. Mikhaylov, Rimma Shelkov, Petr V. Prikhodchenko, Jenny Gun, Yitzhak Wolanov, Luis Cumbal, and Tatiana A. Tripol’skaya
- Subjects
Materials science ,Mechanical Engineering ,Inorganic chemistry ,chemistry.chemical_element ,Nanoparticle ,Zinc ,Condensed Matter Physics ,Peroxide ,Oxygen ,chemistry.chemical_compound ,chemistry ,Mechanics of Materials ,General Materials Science ,Zinc peroxide ,Titration ,Thermal analysis ,Hydrogen peroxide - Abstract
Nanoparticles of zinc peroxide, a well known and convenient solid source of hydrogen peroxide, oxygen or active oxygen species, can be readily regenerated by exposure of zinc oxide to slightly basic hydrogen peroxide solutions after being depleted of their active oxygen peroxide content, and these charge–discharge cycles can be repeated many times. We demonstrate the renewability of zinc peroxide coated mica and neat zinc peroxide powders by permanganometric titration, powder X-ray studies, thermal analysis and Raman spectroscopy, all showing good recovery with a rather small change of properties upon repeated cycling. We believe that renewable zinc peroxide can be useful for rechargeable antibiofouling or antifungal paints, clothing additive, floor coverings and other applications where hydrogen peroxide is slowly depleted and should be reloaded to regain its favorable activity.
- Published
- 2014
50. Phase Change Materials: Doubly Coated, Organic–Inorganic Paraffin Phase Change Materials: Zinc Oxide Coating of Hermetically Encapsulated Paraffins (Adv. Mater. Interfaces 12/2019)
- Author
-
Dmitry A. Grishanov, Ovadia Lev, Petr V. Prikhodchenko, Alexander G. Medvedev, Zhichuan J. Xu, Konstantin A. Sakharov, Sergey Sladkevich, and Alexey A. Mikhaylov
- Subjects
Phase change ,Thermal conductivity ,Materials science ,Coating ,Chemical engineering ,chemistry ,Mechanics of Materials ,Mechanical Engineering ,Organic inorganic ,engineering ,chemistry.chemical_element ,Zinc ,engineering.material - Published
- 2019
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