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Janina Kabatc - One of the best experts on this subject based on the ideXlab platform.

  • Highly efficient UV-Vis light activated three-component photoinitiators composed of tris(trimethylsilyl)silane for polymerization of acrylates
    Polymer Chemistry, 2020
    Co-Authors: Alicja Balcerak, Dominika Kwiatkowska, Katarzyna Iwińska, Janina Kabatc
    Abstract:

    The goal of this paper concerns the evaluation of the efficiency of novel three-component systems for initiating the photopolymerization process of 2-ethyl-2-(hydroxymethyl)-1,3-propanediol triacrylate (TMPTA). Combinations of 1,3-bis(phenylamino)squaraine (SQG1) with different types of co-initiators are proposed as effective UV-Vis light photoinitiators. The co-initiators used in the experiments, such as silane (TTMSS), Borate Salt (B2), carbazole (NVC) and a set of iodonium Salts (I1, I2, I77, I81), are active radical sources for initiation of the polymerization of TMPTA. The effect of the composition of the system on the photopolymerization kinetics was analyzed. The optimal photoinitiator concentration that gives high monomer conversions and high values of the rate of polymerization is indicated and presented in this article.

  • Onium Salts improve the kinetics of photopolymerization of acrylate activated with visible light
    RSC Advances, 2020
    Co-Authors: Janina Kabatc, Zbigniew Czech, Alicja Balcerak, Dominika Kwiatkowska, Katarzyna Iwińska, Agnieszka Skotnicka, Marcin Bartkowiak
    Abstract:

    The aim was study the influence of onium Salts on the kinetics of photopolymerization in the visible light region. Trimethylolpropane triacrylate TMPTA was selected as a monomer, and activated by 1,3-bis(phenylamino)squaraine (SQ) used as a photosensitizer in addition to tetramethylammonium n-butyltriphenylBorate (B2). The iodonium Salt [A–I–B]+X− functioned as a second radical initiator, bearing a different substitution pattern for the cation. The ternary system was formulated with different concentrations of both Borate and diphenyliodonium Salts. Differential scanning calorimetry was used to investigate the polymerization reaction over the photoactivation time carried out at 300 nm < λ < 500 nm irradiation. When the squaraine dye/Borate Salt was used as photoinitiator, a slow polymerization reaction was observed and a lower monomer conversion. The addition of a third component (onium Salt) increased the polymerization rate and conversion. Ternary photoinitiator systems showed improvement in the polymerization rate of triacrylate leading to high conversion in a short photoactivation time. The photoinitiating ability of bi- and tri-component photoinitiators acting in the UV-Vis region for initiation polymerization of triacrylate was compared with those of some commercially used photoinitiating systems. It was also found, that, the parallel electron transfer from an excited state of the sensitizer to [A–I–B]+X−, and an electron transfer from a ground state of R(Ph)3B−N(CH3)4+ to an excited state of the sensitizer results in two types of initiating radical.

  • Two-cationic 2-methylbenzothiazole derivatives as green light absorbed sensitizers in initiation of free radical polymerization
    Colloid and Polymer Science, 2015
    Co-Authors: Janina Kabatc, Katarzyna Kostrzewska, Katarzyna Jurek
    Abstract:

    N -Methylpyridinium esters derivatives of 2-methylbenzothiazole hemicyanine dyes photoinitiators/photosensitizers derived from N -propyl-3-[ N -2-methylbenzothiazolo]-4-pyridyno phenylacetic acid ester diiodide and N -propyl-3-[ N -2-me]thylbenzothiazolo]-4-pyridino diphenylacetic acid ester diiodide were synthesized and proposed as new photoinitiators of polymerization of 2-ethyl-(2-hydroxymethyl)-1,3-propanediol triacrylate under argon laser exposure at 514 nm. These compounds exhibit a strong absorption around 520 nm. The dye/Borate Salt, dye/Borate Salt/ N -methoxypyridinium Salt, dye/Borate Salt/diphenyliodonium Salt, and dye/Borate Salt/1,3,5-triazine derivative combinations are very efficient in initiating of radical photopolymerization of triacrylate. Excellent polymerization profiles were obtained. The effect of both sensitizer and co-initiator structure on the ability to initiate of free radical polymerization of photoinitiating systems was also presented. The mechanism was discussed for different multicomponent initiating systems. Graphical Abstract Two-cationic 2-methylbenzothiazole derivatives as green light absorbed sensitizers in initiation of free radical polymerization.

  • Synthesis, properties, and application of new benzothiazole‐based sensitisers in polymer chemistry
    Coloration Technology, 2015
    Co-Authors: Janina Kabatc, Katarzyna Jurek
    Abstract:

    New photoinitiating systems composed of benzothiazolestyrylium dyes as chromophores and n-butyltriphenylBorate anion as electron donor were prepared and characterised. Photoredox pairs consisting of hemicyanine dyes and organoBorate Salts may act as visible-light photoinitiators for the radical polymerisation of multifunctional acrylates. The efficiences of these photoinitiator systems are based on the free energy changes of an electron transfer from Borate Salt to the dye. Experimental results show that the photoinitiating ability of the photoredox pair tested strongly depends upon the reduction potential of hemicyanine dye, the oxidation potential of Borate Salt, and the structure of the dicationic dye.

  • Two-cationic 2-methylbenzothiazole derivatives as green light absorbed sensitizers in initiation of free radical polymerization.
    Colloid and Polymer Science, 2015
    Co-Authors: Janina Kabatc, Katarzyna Kostrzewska, Katarzyna Jurek
    Abstract:

    N-Methylpyridinium esters derivatives of 2-methylbenzothiazole hemicyanine dyes photoinitiators/photosensitizers derived from N-propyl-3-[N-2-methylbenzothiazolo]-4-pyridyno phenylacetic acid ester diiodide and N-propyl-3-[N-2-me]thylbenzothiazolo]-4-pyridino diphenylacetic acid ester diiodide were synthesized and proposed as new photoinitiators of polymerization of 2-ethyl-(2-hydroxymethyl)-1,3-propanediol triacrylate under argon laser exposure at 514 nm. These compounds exhibit a strong absorption around 520 nm. The dye/Borate Salt, dye/Borate Salt/N-methoxypyridinium Salt, dye/Borate Salt/diphenyliodonium Salt, and dye/Borate Salt/1,3,5-triazine derivative combinations are very efficient in initiating of radical photopolymerization of triacrylate. Excellent polymerization profiles were obtained. The effect of both sensitizer and co-initiator structure on the ability to initiate of free radical polymerization of photoinitiating systems was also presented. The mechanism was discussed for different multicomponent initiating systems.

Jerzy Pączkowski - One of the best experts on this subject based on the ideXlab platform.

  • Photopolymerization reactions initiated by a visible light photoinitiating system : Cyanine dye/Borate Salt/1,3,5-triazine
    Journal of Polymer Science Part A: Polymer Chemistry, 2007
    Co-Authors: Janina Kabatc, Magdalena Zasada, Jerzy Pączkowski
    Abstract:

    New three-component photoinitiating systems consisting of a cyanine dye, Borate Salt, and a 1,3,5-triazine derivative were investigated by measuring their photoinitiation activities and through fluorescence quenching experiments. Polymerization kinetic studies based on the microcalorimetric method revealed a significant increase in polymerization rate when the concentration of n-butyltriphenylBorate Salt or the 1,3,5-triazine derivative were increased. The photo-induced electron transfer process between electron donor and electron acceptor was studied by means of fluorescence quenching and SrEt change of the fluorescence intensity. The experiments performed documented that an increase of the n-butyltriphenylBorate Salt concentration dramatically increases the rate of dye fluorescence quenching, whereas the increasing of the 1,3,5-triazine derivative concentration slows down the consumption of the dye. We conclude that the primary photochemical reaction involves an electron transfer from the n-butyltriphenylBorate anion to the excited singlet state of the dye, followed by the reaction of the 1,3,5-triazine derivative with the resulting dye radical to regenerate the original dye. This reaction simultaneously produces a triazinyl radical anion derived from the 1,3,5-triazine, which undergoes the carbon-halogen bond cleavage yielding radicals active in initiation of a free radical polymerization chain.

  • acceleration of the free radical polymerization by using n alkoxypyridinium Salt as co initiator in hemicyanine dye Borate Salt photoinitiating system
    Journal of Photochemistry and Photobiology A-chemistry, 2006
    Co-Authors: Janina Kabatc, Jerzy Pączkowski
    Abstract:

    Abstract Results of kinetic studies of the two-component and three-component photoinitiator system used in visible-light photoinduced polymerization of 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (TMPTA) are presented. Five different hemicyanine dyes ((6-bromo-3-ethyl-2-( p -alkylamino)styryl) benzothiazolium Salts SBr ) were used as sensitizers in photoinitiator systems, with four different co-initiators. The rates of polymerization were compared with the rate of polymerization photoinitiated by well known photoinitiator composed of hemicyanine dye and n -butyltriphenylBorate anion as co-initiator. Reactive radicals that initiate the polymerization are formed by a mechanism of photoinduced electron transfer process and are different for all co-initiators tested. In this paper we shown that photoinitiator system composed of sensitizer and co-initiator is less efficient to the photoinitiation of free radical polymerization of TMPTA than photoinitiator system possessing dye as sensitizer and two types of co-initiators.

  • Acceleration of the free radical polymerization by using N-alkoxypyridinium Salt as co-initiator in hemicyanine dye/Borate Salt photoinitiating system
    Journal of Photochemistry and Photobiology A-chemistry, 2006
    Co-Authors: Janina Kabatc, Jerzy Pączkowski
    Abstract:

    Abstract Results of kinetic studies of the two-component and three-component photoinitiator system used in visible-light photoinduced polymerization of 2-ethyl-2-(hydroxymethyl)-1,3-propanediol (TMPTA) are presented. Five different hemicyanine dyes ((6-bromo-3-ethyl-2-( p -alkylamino)styryl) benzothiazolium Salts SBr ) were used as sensitizers in photoinitiator systems, with four different co-initiators. The rates of polymerization were compared with the rate of polymerization photoinitiated by well known photoinitiator composed of hemicyanine dye and n -butyltriphenylBorate anion as co-initiator. Reactive radicals that initiate the polymerization are formed by a mechanism of photoinduced electron transfer process and are different for all co-initiators tested. In this paper we shown that photoinitiator system composed of sensitizer and co-initiator is less efficient to the photoinitiation of free radical polymerization of TMPTA than photoinitiator system possessing dye as sensitizer and two types of co-initiators.

Naoki Tanaka - One of the best experts on this subject based on the ideXlab platform.

  • an organic Borate Salt with superior p doping capability for organic semiconductors
    Advanced Science, 2020
    Co-Authors: Naoki Tanaka, Berthold Wegner, Dominique Lungwitz, Ahmed E. Mansour, Claudia E. Tait, Tianshu Zhai, Steffen Duhm, Michael Forster
    Abstract:

    Molecular doping allows enhancement and precise control of electrical properties of organic semiconductors, and is thus of central technological relevance for organic (opto-) electronics. Beyond single-component molecular electron acceptors and donors, organic Salts have recently emerged as a promising class of dopants. However, the pertinent fundamental understanding of doping mechanisms and doping capabilities is limited. Here, the unique capabilities of the Salt consisting of a borinium cation (Mes2B+; Mes: mesitylene) and the tetrakis(penta-fluorophenyl)Borate anion [B(C6F5)4]- is demonstrated as p-type dopant for polymer semiconductors. With a range of experimental methods, the doping mechanism is identified to comprise electron transfer from the polymer to Mes2B+, and the positive charge on the polymer is stabilized by [B(C6F5)4]-. Notably, the former Salt cation leaves during processing and is not present in films. The anion [B(C6F5)4]- even enables the stabilization of polarons and bipolarons in poly(3-hexylthiophene), not yet achieved with other molecular dopants. From doping studies with high ionization energy polymer semiconductors, the effective electron affinity of Mes2B+[B(C6F5)4]- is estimated to be an impressive 5.9 eV. This significantly extends the parameter space for doping of polymer semiconductors.

  • An Organic Borate Salt with Superior p‐Doping Capability for Organic Semiconductors
    Advanced Science, 2020
    Co-Authors: Berthold Wegner, Naoki Tanaka, Dominique Lungwitz, Ahmed E. Mansour, Claudia E. Tait, Tianshu Zhai, Steffen Duhm, Michael Forster, Jan Behrends, Yoshiaki Shoji
    Abstract:

    Molecular doping allows enhancement and precise control of electrical properties of organic semiconductors, and is thus of central technological relevance for organic (opto-) electronics. Beyond single-component molecular electron acceptors and donors, organic Salts have recently emerged as a promising class of dopants. However, the pertinent fundamental understanding of doping mechanisms and doping capabilities is limited. Here, the unique capabilities of the Salt consisting of a borinium cation (Mes2B+; Mes: mesitylene) and the tetrakis(penta-fluorophenyl)Borate anion [B(C6F5)4]- is demonstrated as p-type dopant for polymer semiconductors. With a range of experimental methods, the doping mechanism is identified to comprise electron transfer from the polymer to Mes2B+, and the positive charge on the polymer is stabilized by [B(C6F5)4]-. Notably, the former Salt cation leaves during processing and is not present in films. The anion [B(C6F5)4]- even enables the stabilization of polarons and bipolarons in poly(3-hexylthiophene), not yet achieved with other molecular dopants. From doping studies with high ionization energy polymer semiconductors, the effective electron affinity of Mes2B+[B(C6F5)4]- is estimated to be an impressive 5.9 eV. This significantly extends the parameter space for doping of polymer semiconductors.

  • Formation of environmentally stable hole-doped graphene films with instantaneous and high-density carrier doping via a boron-based oxidant
    npj 2D Materials and Applications, 2019
    Co-Authors: Kaito Kanahashi, Naoki Tanaka, Yoshiaki Shoji, Mina Maruyama, Il Jeon, Kenji Kawahara, Masatou Ishihara, Masataka Hasegawa, Hiromichi Ohta, Hiroki Ago
    Abstract:

    Large-area graphene films have substantial potential for use as next-generation electrodes because of their good chemical stability, high flexibility, excellent carrier mobility, and lightweight structure. However, various issues remain unsolved. In particular, high-density carrier doping within a short time by a simple method, and air stability of doped graphene films, are highly desirable. Here, we demonstrate a solution-based high-density (>1014 cm−2) hole doping approach that promises to push the performance limit of graphene films. The reaction of graphene films with a tetrakis(pentafluorophenyl)Borate Salt, containing a two-coordinate boron cation, achieves doping within an extremely short time (4 s), and the doped graphene films are air stable for at least 31 days. X-ray photoelectron spectroscopy reveals that the graphene films are covered by the chemically stable anions, resulting in an improved stability in air. Moreover, the doping reduces the transmittance by only 0.44 ± 0.23%. The simplicity of the doping process offers a viable route to the large-scale production of functional graphene electrodes. Highly transparent, hole-doped graphene films can be obtained using molecular dopants based on Borate Salts in solution. A team led by Taishi Takenobu at Waseda University and Nagoya University demonstrated a solution-based approach to dope graphene with high carrier density. Graphene samples synthesized by chemical vapor deposition were immersed in a saturated o-dichlorobenzene solution of Mes2B+[(C6F5)4B]−, a tetrakis(pentafluorophenyl)Borate Salt containing a two-coordinate boron cation, Mes2B+, and a counter anion, [(C6F5)4B]−. After rinsing with an organic solvent and annealing, a high hole density of 2.5 × 1014 cm−2 was achieved within 4 seconds. The conduction behavior was stable for at least 31 days in air without a substantial change in resistance, and only a minor reduction of 0.44% in the film transmittance was observed.

  • Formation of environmentally stable hole-doped graphene films with instantaneous and high-density carrier doping via a boron-based oxidant
    Springer Nature, 2019
    Co-Authors: 丸山 実那, Kaito Kanahashi, Naoki Tanaka, Yoshiaki Shoji, Mina Maruyama, Il Jeon, Kenji Kawahara, Masatou Ishihara, 岡田 晋, Masataka Hasegawa
    Abstract:

    Large-area graphene films have substantial potential for use as next-generation electrodes because of their good chemical stability, high flexibility, excellent carrier mobility, and lightweight structure. However, various issues remain unsolved. In particular, high-density carrier doping within a short time by a simple method, and air stability of doped graphene films, are highly desirable. Here, we demonstrate a solution-based high-density (>1014 cm−2) hole doping approach that promises to push the performance limit of graphene films. The reaction of graphene films with a tetrakis(pentafluorophenyl)Borate Salt, containing a two-coordinate boron cation, achieves doping within an extremely short time (4 s), and the doped graphene films are air stable for at least 31 days. X-ray photoelectron spectroscopy reveals that the graphene films are covered by the chemically stable anions, resulting in an improved stability in air. Moreover, the doping reduces the transmittance by only 0.44 ± 0.23%. The simplicity of the doping process offers a viable route to the large-scale production of functional graphene electrodes

  • Formation of environmentally stable hole-doped graphene films with instantaneous and high-density carrier doping via a boron-based oxidant
    Nature Publishing Group, 2019
    Co-Authors: Kaito Kanahashi, Naoki Tanaka, Yoshiaki Shoji, Mina Maruyama, Il Jeon, Kenji Kawahara, Masatou Ishihara, Masataka Hasegawa, Hiromichi Ohta, Hiroki Ago
    Abstract:

    Doped graphene: Borate Salt provides efficient hole doping Highly transparent, hole-doped graphene films can be obtained using molecular dopants based on Borate Salts in solution. A team led by Taishi Takenobu at Waseda University and Nagoya University demonstrated a solution-based approach to dope graphene with high carrier density. Graphene samples synthesized by chemical vapor deposition were immersed in a saturated o-dichlorobenzene solution of Mes2B+[(C6F5)4B]−, a tetrakis(pentafluorophenyl)Borate Salt containing a two-coordinate boron cation, Mes2B+, and a counter anion, [(C6F5)4B]−. After rinsing with an organic solvent and annealing, a high hole density of 2.5 × 1014 cm−2 was achieved within 4 seconds. The conduction behavior was stable for at least 31 days in air without a substantial change in resistance, and only a minor reduction of 0.44% in the film transmittance was observed

Berthold Wegner - One of the best experts on this subject based on the ideXlab platform.

  • An Organic Borate Salt with Superior p‐Doping Capability for Organic Semiconductors
    Advanced Science, 2020
    Co-Authors: Berthold Wegner, Naoki Tanaka, Dominique Lungwitz, Ahmed E. Mansour, Claudia E. Tait, Tianshu Zhai, Steffen Duhm, Michael Forster, Jan Behrends, Yoshiaki Shoji
    Abstract:

    Molecular doping allows enhancement and precise control of electrical properties of organic semiconductors, and is thus of central technological relevance for organic (opto-) electronics. Beyond single-component molecular electron acceptors and donors, organic Salts have recently emerged as a promising class of dopants. However, the pertinent fundamental understanding of doping mechanisms and doping capabilities is limited. Here, the unique capabilities of the Salt consisting of a borinium cation (Mes2B+; Mes: mesitylene) and the tetrakis(penta-fluorophenyl)Borate anion [B(C6F5)4]- is demonstrated as p-type dopant for polymer semiconductors. With a range of experimental methods, the doping mechanism is identified to comprise electron transfer from the polymer to Mes2B+, and the positive charge on the polymer is stabilized by [B(C6F5)4]-. Notably, the former Salt cation leaves during processing and is not present in films. The anion [B(C6F5)4]- even enables the stabilization of polarons and bipolarons in poly(3-hexylthiophene), not yet achieved with other molecular dopants. From doping studies with high ionization energy polymer semiconductors, the effective electron affinity of Mes2B+[B(C6F5)4]- is estimated to be an impressive 5.9 eV. This significantly extends the parameter space for doping of polymer semiconductors.

  • an organic Borate Salt with superior p doping capability for organic semiconductors
    Advanced Science, 2020
    Co-Authors: Naoki Tanaka, Berthold Wegner, Dominique Lungwitz, Ahmed E. Mansour, Claudia E. Tait, Tianshu Zhai, Steffen Duhm, Michael Forster
    Abstract:

    Molecular doping allows enhancement and precise control of electrical properties of organic semiconductors, and is thus of central technological relevance for organic (opto-) electronics. Beyond single-component molecular electron acceptors and donors, organic Salts have recently emerged as a promising class of dopants. However, the pertinent fundamental understanding of doping mechanisms and doping capabilities is limited. Here, the unique capabilities of the Salt consisting of a borinium cation (Mes2B+; Mes: mesitylene) and the tetrakis(penta-fluorophenyl)Borate anion [B(C6F5)4]- is demonstrated as p-type dopant for polymer semiconductors. With a range of experimental methods, the doping mechanism is identified to comprise electron transfer from the polymer to Mes2B+, and the positive charge on the polymer is stabilized by [B(C6F5)4]-. Notably, the former Salt cation leaves during processing and is not present in films. The anion [B(C6F5)4]- even enables the stabilization of polarons and bipolarons in poly(3-hexylthiophene), not yet achieved with other molecular dopants. From doping studies with high ionization energy polymer semiconductors, the effective electron affinity of Mes2B+[B(C6F5)4]- is estimated to be an impressive 5.9 eV. This significantly extends the parameter space for doping of polymer semiconductors.

Agnieszka Celmer - One of the best experts on this subject based on the ideXlab platform.

  • an argon laser induced polymerization photoinitiated by both mono and bichromophoric hemicyanine dye Borate Salt ion pairs the synthesis spectroscopic electrochemical and kinetic studies
    Polymer, 2009
    Co-Authors: Janina Kabatc, Agnieszka Celmer
    Abstract:

    Abstract A series of homodimeric hemicyanine dyes based on (p-dimethylaminostyryl)benzothiazolium, (p-dimethylaminostyryl)benzoxazolium, (p-dimethylaminostyryl)-2,3,3-trimethyl-3H-indolium residues were synthesized. Several photoredox pairs containing mono- and bichromophoric hemicyanine dyes, possessing benzothiazole, benzoxazole or indolinium group linked by 5 or 10 methylene groups have been evaluated as novel photoinitiators for free radical polymerization induced with the argon-ion laser visible emission. In tested photoredox pairs, hemicyanine dye acts as an electron acceptor and it is coupled with Borate anion which is an electron donor. The photochemistry of the series of bichromophoric hemicyanine Borates: 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzothiazolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzothiazolium]decane (S5, S10), 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzoxazolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzoxazolium]decane (O5, O10) and 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)-3,3,3′,3′-tetramethyl-3H-indolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)-3,3,3′,3′-tetramethyl-3H-indolium]decane (I5, I10) was compared to the photochemistry of structurally related monochromophoric hemicyanine Borates (S1, O1, I1).

  • An argon laser induced polymerization photoinitiated by both mono- and bichromophoric hemicyanine dye–Borate Salt ion pairs. The synthesis, spectroscopic, electrochemical and kinetic studies
    Polymer, 2009
    Co-Authors: Janina Kabatc, Agnieszka Celmer
    Abstract:

    Abstract A series of homodimeric hemicyanine dyes based on (p-dimethylaminostyryl)benzothiazolium, (p-dimethylaminostyryl)benzoxazolium, (p-dimethylaminostyryl)-2,3,3-trimethyl-3H-indolium residues were synthesized. Several photoredox pairs containing mono- and bichromophoric hemicyanine dyes, possessing benzothiazole, benzoxazole or indolinium group linked by 5 or 10 methylene groups have been evaluated as novel photoinitiators for free radical polymerization induced with the argon-ion laser visible emission. In tested photoredox pairs, hemicyanine dye acts as an electron acceptor and it is coupled with Borate anion which is an electron donor. The photochemistry of the series of bichromophoric hemicyanine Borates: 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzothiazolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzothiazolium]decane (S5, S10), 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzoxazolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)benzoxazolium]decane (O5, O10) and 1,5-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)-3,3,3′,3′-tetramethyl-3H-indolium]pentane, 1,10-bis-[N,N′-(2,2′-(4-N,N-dimethylamino)styryl)-3,3,3′,3′-tetramethyl-3H-indolium]decane (I5, I10) was compared to the photochemistry of structurally related monochromophoric hemicyanine Borates (S1, O1, I1).