Viologen

14,000,000 Leading Edge Experts on the ideXlab platform

Scan Science and Technology

Contact Leading Edge Experts & Companies

Scan Science and Technology

Contact Leading Edge Experts & Companies

The Experts below are selected from a list of 8361 Experts worldwide ranked by ideXlab platform

Rong-guang Lin - One of the best experts on this subject based on the ideXlab platform.

  • photochromic hybrid containing in situ generated benzyl Viologen and novel trinuclear bi3cl14 5 improved photoresponsive behavior by the π π interactions and size effect of inorganic oligomer
    Inorganic Chemistry, 2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radi...

  • Photochromic Hybrid Containing In Situ-Generated Benzyl Viologen and Novel Trinuclear [Bi3Cl14]5–: Improved Photoresponsive Behavior by the π···π Interactions and Size Effect of Inorganic Oligomer
    2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radical but also the second electron-transfer pathway, from a π-conjugated substituent to a Viologen cation, for the photochromic process

Guo-cong Guo - One of the best experts on this subject based on the ideXlab platform.

  • photochromic hybrid containing in situ generated benzyl Viologen and novel trinuclear bi3cl14 5 improved photoresponsive behavior by the π π interactions and size effect of inorganic oligomer
    Inorganic Chemistry, 2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radi...

  • Photochromic Hybrid Containing In Situ-Generated Benzyl Viologen and Novel Trinuclear [Bi3Cl14]5–: Improved Photoresponsive Behavior by the π···π Interactions and Size Effect of Inorganic Oligomer
    2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radical but also the second electron-transfer pathway, from a π-conjugated substituent to a Viologen cation, for the photochromic process

Hiroto Murakami - One of the best experts on this subject based on the ideXlab platform.

  • electrochromism of ferrocene and Viologen based redox active ionic liquids composite
    ACS Applied Materials & Interfaces, 2019
    Co-Authors: Hironobu Tahara, Kazuaki Uranaka, Makoto Hirano, Tomoya Ikeda, Takamasa Sagara, Hiroto Murakami
    Abstract:

    Redox-active ionic liquids (RAILs) require no other additional reagents such as solvent and supporting electrolyte for electrochemical reactions under undiluted condition. Viologen-based RAILs are one of the electrochromic (EC) ionic liquids with sharp color contrast and high chemical stability. An operation of an EC cell requires two electroactive elements, an EC material and a charge compensating material. In this study, an equimolar composite of a Viologen-based RAIL as the EC material and a ferrocene-based RAIL as the charge compensation material, was synthesized and applied to an EC cell. The EC cell with the composite RAIL of as high concentration as 0.92 M each redox species showed good coloration efficiency (91.4 cm2 C–1 at 540 nm on 1.0 V). The coloration process of the EC cell was diffusion-limited process. The current and absorbance of the EC cell reached constant values at large enough bias voltage because of the charge recombination between reduced Viologens and oxidized ferrocenes. The recom...

  • Electrochromism of Ferrocene- and Viologen-Based Redox-Active Ionic Liquids Composite
    2018
    Co-Authors: Hironobu Tahara, Kazuaki Uranaka, Makoto Hirano, Tomoya Ikeda, Takamasa Sagara, Hiroto Murakami
    Abstract:

    Redox-active ionic liquids (RAILs) require no other additional reagents such as solvent and supporting electrolyte for electrochemical reactions under undiluted condition. Viologen-based RAILs are one of the electrochromic (EC) ionic liquids with sharp color contrast and high chemical stability. An operation of an EC cell requires two electroactive elements, an EC material and a charge compensating material. In this study, an equimolar composite of a Viologen-based RAIL as the EC material and a ferrocene-based RAIL as the charge compensation material, was synthesized and applied to an EC cell. The EC cell with the composite RAIL of as high concentration as 0.92 M each redox species showed good coloration efficiency (91.4 cm2 C–1 at 540 nm on 1.0 V). The coloration process of the EC cell was diffusion-limited process. The current and absorbance of the EC cell reached constant values at large enough bias voltage because of the charge recombination between reduced Viologens and oxidized ferrocenes. The recombination affected rapid color erasing process. Almost no deterioration of the composite RAIL was found by 1H NMR after 13 000 potential cycle durability experiment

Angel E Kaifer - One of the best experts on this subject based on the ideXlab platform.

  • electrochemistry of Viologen dications in cholate media and competition between the cholate assemblies and the cucurbit 7 uril host
    Langmuir, 2015
    Co-Authors: Beijun Cheng, Angel E Kaifer
    Abstract:

    The cathodic voltammetric behavior of N,N′-dimethyl-4,4′-bipyridinium (methylViologen, MV2+), N,N′-dipropyl-4,4′-bipyridinium (propylViologen, PV2+), N,N′-dibutyl-4,4′-bipyridinium (butylViologen, BV2+), and N-heptyl-N′-ethyl-4,4′-bipyridinium (heptyl-ethylViologen, HEV2+) was investigated in aqueous solution containing variable concentrations of sodium cholate. In general, the presence of cholate was found to solubilize the more hydrophobic forms of the Viologen probes. Among the three accessible Viologen oxidation states (V2+, V+•, and V), the intermediate cation radical (V+•) was preferentially stabilized by the cholate aggregates regardless of the nature of the N-alkyl substituents. This stabilization leads to anodic shifts in the first half-wave potential (V2+/V+•) and cathodic shifts in the second half-wave potential (V+•/V) for Viologen reduction. Both potential shifts were considerably more pronounced as the hydrophobic character of the Viologen probe increased. The presence of the cucurbit[7]uril...

  • cucurbiturils as versatile receptors for redox active substrates
    Israel Journal of Chemistry, 2011
    Co-Authors: Angel E Kaifer
    Abstract:

    Research on the chemistry of cucurbit[n]uril (CBn) hosts has picked up and maintained an impressive pace in the last decade, primarily due to the isolation of hosts with relatively larger cavity sizes, such as CB7 and CB8. This review article summarizes our involvement in this research effort, with particular emphasis on the binding of redox active guests by the CB7 and CB8 hosts. The binding of 4,4′-bipyridinium (Viologen) derivatives was the starting point of our CB research. While methylViologen is encapsulated by CB7, forming a highly symmetric inclusion complex, more hydrophobic Viologens are bound by inclusion of one of the terminal N-substituents inside the host cavity. Cationic ferrocene derivatives reach extremely high binding affinities with CB7. Binding by CB8 offers additional possibilities, since this host may accommodate two aromatic units inside its cavity, which can be utilized to exert redox control on the assembly of suitably dendronized guests. From a purely electrochemical standpoint, CB7-included Viologens maintain their voltammetric reversibility, but CB7-included ferrocene residues experience a pronounced attenuation of their electron transfer kinetics. We have also applied these binding and electrochemical properties to the design and preparation of switchable, CB-based pseudorotaxanes.

  • encapsulation of ferrocene and peripheral electrostatic attachment of Viologens to dimeric molecular capsules formed by an octaacid deep cavity cavitand
    Chemistry: A European Journal, 2008
    Co-Authors: Dagmara Podkoscielny, Ivy Philip, Corinne L D Gibb, Bruce C Gibb, Angel E Kaifer
    Abstract:

    In aqueous media the deep-cavity cavitand octaacid 1 forms stable dimeric molecular capsules 1 2 , which are stabilized by hydrophobic effects. In this work we investigate the binding interactions in aqueous solution between these capsules and the redox active guests, ferrocene (Fc) and three 4,4'-bipyridinium (Viologen) dications: methyl Viologen (MV 2+ ), ethyl Viologen (EV 2+ ),and butyl Viologen (BV 2+ ). Using NMR spectroscopic and electrochemical techniques we clearly show that the hydrophobic Fc guest is encapsulated inside 1 2 . An interesting effect of this encapsulation is that the reversible voltammetric response of Fc is completely eliminated when it resides inside the 1 2 capsular assembly, a finding that is attributed to very slow electrochemical kinetics for the oxidation of Fc@1 2 . Diffusion coefficient measurements (PGSE NMR spectroscopy) reveal that all three Viologen guests are strongly bound to the dimeric capsules. However, the 1 H NMR spectroscopic data are not consistent with encapsulation and the measured diffusion coefficients indicate that two Viologen guests can strongly associate with a single dimeric capsule. Furthermore, the (V 2+ ) 2 . 1 2 complex is capable of encapsulating ferrocene, clearly suggesting that the Viologen guests are bound externally, via coulombic interactions, to the anionic polar ends of the capsule. The electrochemical kinetic rate constants for the reduction of the Viologen residue in the V 2+ .1 2 complexes were measured and found to be substantially lower than those for the free Viologen guests.

Ming-sheng Wang - One of the best experts on this subject based on the ideXlab platform.

  • photochromic hybrid containing in situ generated benzyl Viologen and novel trinuclear bi3cl14 5 improved photoresponsive behavior by the π π interactions and size effect of inorganic oligomer
    Inorganic Chemistry, 2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radi...

  • Photochromic Hybrid Containing In Situ-Generated Benzyl Viologen and Novel Trinuclear [Bi3Cl14]5–: Improved Photoresponsive Behavior by the π···π Interactions and Size Effect of Inorganic Oligomer
    2014
    Co-Authors: Rong-guang Lin, Ming-sheng Wang, Guo-cong Guo
    Abstract:

    Two new member of (V)(2n+2)/2[Bi2nCl8n+2] series hybrids, (BzV)2[Bi2Cl10] (1) and (BzV)5[Bi3Cl14]2·(C6H5CH2)2O (2) (where BzV2+ = N,N′-dibenzyl-4,4′-bipyridinium and (C6H5CH2)2O = dibenzyl ether) have been obtained, and compound 2 contains an unprecedented discrete trimer [Bi3Cl14]5– counterion. The novel in situ-synthesized symmetric Viologen cation with aromatic groups on both sides of 4,4′-bipy would provide more opportunities to create π···π interactions to optimize the photochromic property of the hybrid, and different bismuthated-halide oligomers enable us to discuss the size effect in this series of compounds. Both 1 and 2 are photochromic, and their photoresponsive rate is faster than that of reported Viologen–metal halide hybrids. Experimental and theoretical data illustrated that the size of the inorganic oligomer can significantly influence the photoresponsive rate of the Viologen dication, and the π···π interaction behaves as not only a powerful factor to stabilize the Viologen monocation radical but also the second electron-transfer pathway, from a π-conjugated substituent to a Viologen cation, for the photochromic process