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Vereshchagin AA, Volkov AI, Novoselova JV, Panjwani NA, Yankin AN, Sizov VV, Lukyanov DA, Behrends J, Levin OV. Harmonizing Energies: The Interplay Between a Nonplanar SalEn-Type Molecule and a TEMPO Moiety in a New Hybrid Energy-Storing Redox-Conducting Polymer. Macromol Rapid Commun 2024; 45:e2400074. [PMID: 38593474 DOI: 10.1002/marc.202400074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2024] [Revised: 03/19/2024] [Indexed: 04/11/2024]
Abstract
Redox-conducting polymers based on SalEn-type complexes have attracted considerable attention due to their potential applications in electrochemical devices. However, their charge transfer mechanisms, physical and electrochemical properties remain unclear, hindering their rational design and optimization. This study aims to establish the influence of monomer geometry on the polymer's properties by investigating the properties of novel nonplanar SalEn-type complexes, poly[N,N'-bis(salicylidene)propylene-2-(hydroxy)diaminonickel(II)], and its analog with 2,2,6,6-tetramethylpiperidinyl-N-oxyl (TEMPO)-substituted bridge (MTS). To elucidate the charge transfer mechanism, operando UV-Vis spectroelectrochemical analysis, electrochemical impedance spectroscopy, and electron paramagnetic resonance are employed. Introducing TEMPO into the bridge moiety enhanced the specific capacity of the poly(MTS) material to 95 mA h g-1, attributed to TEMPO's and conductive backbone's charge storage capabilities. Replacement of the ethylenediimino-bridge with a 1,3-propylenediimino- bridge induced significant changes in the complex geometry and material's morphology, electrochemical, and spectral properties. At nearly the same potential, polaron and bipolaron particles emerged, suggesting intriguing features at the overlap point of the electroactivity potentials ranges of polaron-bipolaron and TEMPO, such as a disruption in the connection between TEMPO and the conjugation chain or intramolecular charge transfer. These results offer valuable insights for optimizing strategies to create organic materials with tailored properties for use in catalysis and battery applications.
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Affiliation(s)
- Anatoliy A Vereshchagin
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
- Berlin Joint EPR Lab, Fachbereich Physik Freie Universität Berlin, 14195, Berlin, Germany
| | - Alexey I Volkov
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Julia V Novoselova
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Naitik A Panjwani
- Berlin Joint EPR Lab, Fachbereich Physik Freie Universität Berlin, 14195, Berlin, Germany
| | - Andrei N Yankin
- ITMO University Kronverksky Pr. 49, bldg. A, St. Petersburg, 197101, Russia
| | - Vladimir V Sizov
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Daniil A Lukyanov
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Jan Behrends
- Berlin Joint EPR Lab, Fachbereich Physik Freie Universität Berlin, 14195, Berlin, Germany
| | - Oleg V Levin
- Saint Petersburg State University 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
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Uncovering the mechanism of water-promoted electrochemical degradation of NiSalen polymers. J Electroanal Chem (Lausanne) 2023. [DOI: 10.1016/j.jelechem.2023.117310] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/09/2023]
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3
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Novozhilova M, Polozhentseva J, Karushev M. Asymmetric Monomer Design Enables Structural Control of M(Salen)-Type Polymers. Polymers (Basel) 2023; 15:polym15051127. [PMID: 36904368 PMCID: PMC10007425 DOI: 10.3390/polym15051127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2022] [Revised: 02/05/2023] [Accepted: 02/21/2023] [Indexed: 03/12/2023] Open
Abstract
Conductive and electrochemically active polymers consisting of Salen-type metal complexes as building blocks are of interest for energy storage and conversion applications. Asymmetric monomer design is a powerful tool for fine-tuning the practical properties of conductive electrochemically active polymers but has never been employed for polymers of M(Salen)]. In this work, we synthesize a series of novel conducting polymers composed of a nonsymmetrical electropolymerizable copper Salen-type complex (Cu(3-MeOSal-Sal)en). We show that asymmetrical monomer design provides easy control of the coupling site via polymerization potential control. With in-situ electrochemical methods such as UV-vis-NIR (ultraviolet-visible-near infrared) spectroscopy, EQCM (electrochemical quartz crystal microbalance), and electrochemical conductivity measurements, we elucidate how the properties of these polymers are defined by chain length, order, and cross-linking. We found that the highest conductivity in the series has a polymer with the shortest chain length, which emphasizes the importance of intermolecular iterations in polymers of [M(Salen)].
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Affiliation(s)
- Maria Novozhilova
- Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Ioffe Institute), 26 Polytekhnicheskaya Str., 194021 St. Petersburg, Russia
| | - Julia Polozhentseva
- Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Ioffe Institute), 26 Polytekhnicheskaya Str., 194021 St. Petersburg, Russia
| | - Mikhail Karushev
- Ioffe Physical-Technical Institute of the Russian Academy of Sciences (Ioffe Institute), 26 Polytekhnicheskaya Str., 194021 St. Petersburg, Russia
- Independent Researcher, Astana 020000, Kazakhstan
- Correspondence:
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In-Situ EC-AFM Study of Electrochemical P-Doping of Polymeric Nickel(II) Complexes with Schiff base Ligands. INORGANICS 2023. [DOI: 10.3390/inorganics11010041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Conductive electrochemically active metallopolymers are outstanding materials for energy storage and conversion, electrocatalysis, electroanalysis, and other applications. The hybrid inorganic–organic nature of these materials ensures their rich chemistry and offers wide opportunities for fine-tuning their functional properties. The electrochemical modulation of the nanomechanical properties of metallopolymers is rarely investigated, and the correlations between the structure, stiffness, and capacitive properties of these materials have not yet been reported. We use electrochemical atomic force microscopy (EC-AFM) to perform in-situ quantitative nanomechanical measurements of two Schiff base metallopolymers, poly[NiSalphen] and its derivative that contains two methoxy substituents in the bridging phenylene diimine unit poly[NiSalphen(CH3O)2], during their polarization in the electrolyte solution to the undoped and fully doped states. We also get insight into the electrochemical p-doping of these polymers using electrochemical quartz crystal microgravimetry (EQCM) coupled with cyclic voltammetry (CV). Combined findings for the structurally similar polymers with different interchain interactions led us to propose a correlation between Young’s modulus of the material, its maximum doping level, and ion and solvent fluxes in the polymer films upon electrochemical oxidation.
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Lukyanov DA, Sizov VV, Volkov AI, Beletskii EV, Yankin AN, Alekseeva EV, Levin OV. Tuning the Charge Transport in Nickel Salicylaldimine Polymers by the Ligand Structure. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27248798. [PMID: 36557930 PMCID: PMC9787065 DOI: 10.3390/molecules27248798] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/05/2022] [Revised: 12/04/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022]
Abstract
The conductivity of the polymeric energy storage materials is the key factor limiting their performance. Conductivity of polymeric NiSalen materials, a prospective class of energy storage materials, was found to depend strongly on the length of the bridge between the nitrogen atoms of the ligand. Polymers obtained from the complexes containing C3 alkyl and hydroxyalkyl bridges showed an electrical conductivity one order of magnitude lower than those derived from more common complexes with C2 alkyl bridges. The observed difference was studied by means of cyclic voltammetry on interdigitated electrodes and operando spectroelectrochemistry, combined with density functional theory (DFT) calculations.
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Affiliation(s)
- Daniil A. Lukyanov
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
| | - Vladimir V. Sizov
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
| | - Alexey I. Volkov
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
| | - Evgenii V. Beletskii
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
| | - Andrey N. Yankin
- School of Physics and Engineering, ITMO University, Kronverksky Pr. 49A, 197101 St. Petersburg, Russia
| | - Elena V. Alekseeva
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
| | - Oleg V. Levin
- Institute of Chemistry, Saint Petersburg University, 199034 St. Petersburg, Russia
- Correspondence: ; Tel.: +7-(812)-4286900
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N,N′-4,5-Dimethoxy-1,2-phenylenebis(salicylideneiminato)nickel(II). MOLBANK 2022. [DOI: 10.3390/m1512] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/05/2022] Open
Abstract
The title compound, which is potentially interesting as a building block for electrochemically active metallopolymers, was synthesized and characterized by single-crystal X-ray diffraction, IR and NMR spectroscopies.
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Spectroelectrochemistry of Electroactive Polymer Composite Materials. Polymers (Basel) 2022; 14:polym14153201. [PMID: 35956715 PMCID: PMC9370871 DOI: 10.3390/polym14153201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/29/2022] [Accepted: 08/02/2022] [Indexed: 02/06/2023] Open
Abstract
In this review, we have summarized the main advantages of the method of spectroelectrochemistry as applied to recent studies on electrosynthesis and redox processes of electroactive polymer composite materials, which have found wide application in designing organic optoelectronic devices, batteries and sensors. These polymer composites include electroactive polymer complexes with large unmovable dopant anions such as polymer electrolytes, organic dyes, cyclodextrins, poly(β-hydroxyethers), as well as polymer-inorganic nanocomposites. The spectroelectrochemical methods reviewed include in situ electron absorption, Raman, infrared and electron spin resonance spectroscopies.
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den Hartog S, Neukermans S, Samanipour M, Ching HV, Breugelmans T, Hubin A, Ustarroz J. Electrocatalysis under a magnetic lens: A combined electrochemistry and electron paramagnetic resonance review. Electrochim Acta 2022. [DOI: 10.1016/j.electacta.2021.139704] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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9
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Reversible Redox Processes in Polymer of Unmetalated Salen-Type Ligand: Combined Electrochemical in Situ Studies and Direct Comparison with Corresponding Nickel Metallopolymer. Int J Mol Sci 2022; 23:ijms23031795. [PMID: 35163715 PMCID: PMC8836782 DOI: 10.3390/ijms23031795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2021] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 11/17/2022] Open
Abstract
Most non-metalized Salen-type ligands form passivation thin films on electrode surfaces upon electrochemical oxidation. In contrast, the H2(3-MeOSalen) forms electroactive polymer films similarly to the corresponding nickel complex. There are no details of electrochemistry, doping mechanism and charge transfer pathways in the polymers of pristine Salen-type ligands. We studied a previously uncharacterized electrochemically active polymer of a Salen-type ligand H2(3-MeOSalen) by a combination of cyclic voltammetry, in situ ultraviolet-visible (UV-VIS) spectroelectrochemistry, in situ electrochemical quartz crystal microbalance and Fourier Transform infrared spectroscopy (FTIR) spectroscopy. By directly comparing it with the polymer of a Salen-type nickel complex poly-Ni(3-MeOSalen) we elucidate the effect of the central metal atom on the structure and charge transport properties of the electrochemically doped polymer films. We have shown that the mechanism of charge transfer in the polymeric ligand poly-H2(3-MeOSalen) are markedly different from the corresponding polymeric nickel complex. Due to deviation from planarity of N2O2 sphere for the ligand H2(3-MeOSalen), the main pathway of electron transfer in the polymer film poly-H2(3-MeOSalen) is between π-stacked structures (the π-electronic systems of phenyl rings are packed face-to-face) and C-C bonded phenyl rings. The main way of electron transfer in the polymer film poly-Ni(3-MeOSalen) is along the polymer chain, while redox processes are ligand-based.
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Lukyanov DA, Vereshchagin AA, Beletskii EV, Atangulov AB, Yankin AN, Sizov VV, Levin OV. Nickel Salicylideniminato 1D MOFs
via
Electrochemical Polymerization. ChemElectroChem 2022. [DOI: 10.1002/celc.202101316] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Daniil A. Lukyanov
- Saint Petersburg University 7/9 Universitetskaya nab. St. Petersburg 199034 Russian Federation
| | | | - Evgenii V. Beletskii
- Saint Petersburg University 7/9 Universitetskaya nab. St. Petersburg 199034 Russian Federation
| | - Arslan B. Atangulov
- Saint Petersburg University 7/9 Universitetskaya nab. St. Petersburg 199034 Russian Federation
| | - Andrei N. Yankin
- ITMO University Kronverksky Pr. 49, bldg. A St. Petersburg 197101 Russian Federation
| | - Vladimir V. Sizov
- Saint Petersburg University 7/9 Universitetskaya nab. St. Petersburg 199034 Russian Federation
| | - Oleg V. Levin
- Saint Petersburg University 7/9 Universitetskaya nab. St. Petersburg 199034 Russian Federation
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A Novel Cobalt Metallopolymer with Redox-Matched Conjugated Organic Backbone via Electropolymerization of a Readily Available N 4 Cobalt Complex. Polymers (Basel) 2021; 13:polym13101667. [PMID: 34065450 PMCID: PMC8161072 DOI: 10.3390/polym13101667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2021] [Revised: 05/07/2021] [Accepted: 05/18/2021] [Indexed: 11/17/2022] Open
Abstract
Fast and reversible cobalt-centered redox reactions in metallopolymers are the key to using these materials in energy storage, electrocatalytic, and sensing applications. Metal-centered electrochemical activity can be enhanced via redox matching of the conjugated organic backbone and cobalt centers. In this study, we present a novel approach to redox matching via modification of the cobalt coordination site: a conductive electrochemically active polymer was electro-synthesized from [Co(Amben)] complex (Amben = N,N′-bis(o-aminobenzylidene)ethylenediamine) for the first time. The poly-[Co(Amben)] films were investigated by cyclic voltammetry, electrochemical quartz crystal microbalance (EQCM), in situ UV-vis-NIR spectroelectrochemistry, and in situ conductance measurements between −0.9 and 1.3 V vs. Ag/Ag+. The polymer displayed multistep redox processes involving reversible transfer of the total of 1.25 electrons per repeat unit. The findings indicate consecutive formation of three redox states during reversible electrochemical oxidation of the polymer film, which were identified as benzidine radical cations, Co(III) ions, and benzidine di-cations. The Co(II)/Co(III) redox switching is retained in the thick polymer films because it occurs at potentials of high polymer conductivity due to the optimum redox matching of the Co(II)/Co(III) redox pair with the organic conjugated backbone. It makes poly-[Co(Amben)] suitable for various practical applications based on cobalt-mediated redox reactions.
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Karushev M, Smirnova E, Chepurnaya I. Nickel(II) Complex of N 4 Schiff Base Ligand as a Building Block for a Conducting Metallopolymer with Multiple Redox States. Molecules 2021; 26:molecules26092646. [PMID: 33946577 PMCID: PMC8124806 DOI: 10.3390/molecules26092646] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 04/27/2021] [Accepted: 04/28/2021] [Indexed: 11/30/2022] Open
Abstract
Metal–ligand interactions in monomeric and polymeric transition metal complexes of Schiff base ligands largely define their functional properties and perspective applications. In this study, redox behavior of a nickel(II) N4-anilinosalen complex, [NiAmben] (where H2Amben = N,N′-bis(o-aminobenzylidene)ethylenediamine) was studied by cyclic voltammetry in solvents of different Lewis basicity. A poly-[NiAmben] film electrochemically synthesized from a 1,2-dichloroethane-based electrolyte was investigated by a combination of cyclic voltammetry, electrochemical quartz crystal microbalance, in situ UV-Vis spectroelectrochemistry, and in situ conductance measurements between −0.9 and 1.3 V vs. Ag/Ag+. The polymer displayed multistep redox processes involving reversible transfer of the total of ca. 1.6 electrons per repeat unit, electrical conductivity over a wide potential range, and multiple color changes in correlation with electrochemical processes. Performance advantages of poly-[NiAmben] over its nickel(II) N2O2 Schiff base analogue were identified and related to the increased number of accessible redox states in the polymer due to the higher extent of electronic communication between metal ions and ligand segments in the nickel(II) N4-anilinosalen system. The obtained results suggest that electrosynthesized poly-[NiAmben] films may be viable candidates for energy storage and saving applications.
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Electrochemical synthesis and characterization of poly [Ni(CH3Osalen)] with immobilized poly(styrenesulfonate) anion dopants. Electrochim Acta 2021. [DOI: 10.1016/j.electacta.2020.137637] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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Novozhilova M, Anischenko D, Chepurnaya I, Dmitrieva E, Malev V, Timonov A, Karushev M. Metal-centered redox activity in a polymeric Cobalt(II) complex of a sterically hindered salen type ligand. Electrochim Acta 2020. [DOI: 10.1016/j.electacta.2020.136496] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Chepurnaya IA, Karushev MP, Alekseeva EV, Lukyanov DA, Levin OV. Redox-conducting polymers based on metal-salen complexes for energy storage applications. PURE APPL CHEM 2020. [DOI: 10.1515/pac-2019-1218] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Metal-salen polymers are electrochemically active metallopolymers functionalized with multiple redox centers, with a potential for high performance in various fields such as heterogeneous catalysis, chemical sensors, energy conversion, saving, and storage. In light of the growing world demand for the development of superior energy storage systems, the prospects of employing these polymers for advancing the performance of supercapacitors and lithium-ion batteries are particularly interesting. This article provides a general overview of the results of investigating key structure-property relationships of metal-salen polymers and using them to design polymer-modified electrodes with improved energy storage characteristics. The results of independent and collaborative studies conducted by the members of two research groups currently affiliated to the Saint–Petersburg State University and the Ioffe Institute, respectively, along with the related data from other studies are presented in this review.
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Affiliation(s)
| | | | - Elena V. Alekseeva
- Institute of Chemistry, Saint Petersburg State University , Saint Petersburg , Russian Federation
| | - Daniil A. Lukyanov
- Institute of Chemistry, Saint Petersburg State University , Saint Petersburg , Russian Federation
| | - Oleg V. Levin
- Institute of Chemistry, Saint Petersburg State University , Saint Petersburg , Russian Federation
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Malev VV, Vorotyntsev MA, Anishchenko DV, Timonov AM. Thermodynamic and kinetic aspects of charge transfer inside conducting polymer films. J Solid State Electrochem 2020. [DOI: 10.1007/s10008-020-04549-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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17
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Dmitrieva EA, Chepurnaya IA, Karushev MP, Timonov AM. The Nature of Charge Carriers in Polymeric Complexes of Nickel with Schiff Bases Containing Electron-Withdrawing Substituents. RUSS J ELECTROCHEM+ 2019. [DOI: 10.1134/s1023193519110041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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18
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Łępicka K, Pieta P, Francius G, Walcarius A, Kutner W. Structure-reactivity requirements with respect to nickel-salen based polymers for enhanced electrochemical stability. Electrochim Acta 2019. [DOI: 10.1016/j.electacta.2019.05.075] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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O'Meara C, Karushev MP, Polozhentceva IA, Dharmasena S, Cho H, Yurkovich BJ, Kogan S, Kim JH. Nickel-Salen-Type Polymer as Conducting Agent and Binder for Carbon-Free Cathodes in Lithium-Ion Batteries. ACS APPLIED MATERIALS & INTERFACES 2019; 11:525-533. [PMID: 30540164 DOI: 10.1021/acsami.8b13742] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Systematic physical and electrochemical characterizations revealed unique positive multifunction of a polymeric salen-type nickel(II) complex, poly[Ni(CH3-salen)], as an additive for conventional cathodes in lithium-ion batteries. Due to its promising electrochemical and mechanical properties, combined with its unique three-dimensional weblike electron-network structure, the redox-active-organometallic polymer can eliminate conductive carbon and replace a significant portion of the poly(vinylidene fluoride) (PVdF) binder that has been used in conventional LiFePO4 cathodes. By replacing such electrochemically inactive components (i.e., carbon and PVdF), LiFePO4 cathodes with poly[Ni(CH3-salen)] deliver improved energy density compared with the conventional LiFePO4 cathode. Facile electron transfer via large-area contact at polymer/LiFePO4 interfaces significantly accelerates charge-transfer reactions and consequently improves the rate capability of the cathodes. In addition, unlike PVdF, poly[Ni(CH3-salen)] retains steady Young's modulus values after immersing in an electrolyte solvent, which enhances the mechanical integrity of the cathodes during the cycling of battery cells and thereby improves their cycle life. The unique multifunction of the poly[Ni(CH3-salen)] will be of broad interest for its application in next-generation energy-storage devices.
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Affiliation(s)
- Cody O'Meara
- Center for Automotive Research, Department of Mechanical and Aerospace Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
| | | | | | - Sajith Dharmasena
- Center for Automotive Research, Department of Mechanical and Aerospace Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Hanna Cho
- Center for Automotive Research, Department of Mechanical and Aerospace Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
| | - Benjamin J Yurkovich
- Center for Automotive Research, Department of Mechanical and Aerospace Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
- Powermers Inc. , Westerville , Ohio 43082 , United States
| | - Sam Kogan
- Powermers Inc. , Westerville , Ohio 43082 , United States
| | - Jung-Hyun Kim
- Center for Automotive Research, Department of Mechanical and Aerospace Engineering , The Ohio State University , Columbus , Ohio 43210 , United States
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