Effects of differently shaped silver nanoparticles on the photophysics of pyridylsulfanyl-substituted phthalocyanines
- D'Souza, Sarah, Mashazi, Philani N, Britton, Jonathan, Nyokong, Tebello
- Authors: D'Souza, Sarah , Mashazi, Philani N , Britton, Jonathan , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193564 , vital:45348 , xlink:href="https://doi.org/10.1016/j.poly.2015.06.038"
- Description: This paper reports on the photophysical behavior of (2-pyridylsulfanyl)phthalocyaninato zinc(II) and 2,9(10),16(17),23(24)-tetra-(2-pyridylsulfanyl)phthalocyaninato zinc(II) in the presence of differently shaped silver nanoparticles (nanospheres, nanotriangles and nanoflowers). The presence of shaped nanoparticles increased both triplet quantum yields and lifetimes of the tetra-substituted mercaptopyridine zinc phthalocyanine in DMSO. It is apparent from this work that the shape of the silver nanoparticle used is of little consequence in influencing photophysical behavior of the phthalocyanines.
- Full Text:
- Date Issued: 2015
- Authors: D'Souza, Sarah , Mashazi, Philani N , Britton, Jonathan , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193564 , vital:45348 , xlink:href="https://doi.org/10.1016/j.poly.2015.06.038"
- Description: This paper reports on the photophysical behavior of (2-pyridylsulfanyl)phthalocyaninato zinc(II) and 2,9(10),16(17),23(24)-tetra-(2-pyridylsulfanyl)phthalocyaninato zinc(II) in the presence of differently shaped silver nanoparticles (nanospheres, nanotriangles and nanoflowers). The presence of shaped nanoparticles increased both triplet quantum yields and lifetimes of the tetra-substituted mercaptopyridine zinc phthalocyanine in DMSO. It is apparent from this work that the shape of the silver nanoparticle used is of little consequence in influencing photophysical behavior of the phthalocyanines.
- Full Text:
- Date Issued: 2015
Effects of gold nanoparticle shape on the aggregation and fluorescence behaviour of water soluble zinc phthalocyanines
- D'Souza, Sarah, Moeno, Sharon, Antunes, Edith M, Nyokong, Tebello
- Authors: D'Souza, Sarah , Moeno, Sharon , Antunes, Edith M , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232500 , vital:49997 , xlink:href="https://doi.org/10.1039/C3NJ00146F"
- Description: The absorption and fluorescence response as well as the fluorescence quantum yields and lifetimes of sulfonated phthalocyanines and alkyl carboxylic acid substituted zinc phthalocyanines in the presence of differently shaped water soluble gold nanoparticles were studied. The respective phthalocyanines are known to be highly aggregated in water, which is reported to markedly reduce the excited state lifetimes. This paper shows that in the presence of star shaped gold nanoparticles, the degree of phthalocyanine aggregation in water is greatly reduced, but the aggregation status of the phthalocyanines does not change for spherical Au nanoparticles. Since gold nanoparticles have already proven to be useful in numerous nanomedicinal and nanomedical applications, the disaggregation of phthalocyanines is an added advantage.
- Full Text:
- Date Issued: 2013
- Authors: D'Souza, Sarah , Moeno, Sharon , Antunes, Edith M , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232500 , vital:49997 , xlink:href="https://doi.org/10.1039/C3NJ00146F"
- Description: The absorption and fluorescence response as well as the fluorescence quantum yields and lifetimes of sulfonated phthalocyanines and alkyl carboxylic acid substituted zinc phthalocyanines in the presence of differently shaped water soluble gold nanoparticles were studied. The respective phthalocyanines are known to be highly aggregated in water, which is reported to markedly reduce the excited state lifetimes. This paper shows that in the presence of star shaped gold nanoparticles, the degree of phthalocyanine aggregation in water is greatly reduced, but the aggregation status of the phthalocyanines does not change for spherical Au nanoparticles. Since gold nanoparticles have already proven to be useful in numerous nanomedicinal and nanomedical applications, the disaggregation of phthalocyanines is an added advantage.
- Full Text:
- Date Issued: 2013
Effects of number of ring substituents on the physicochemical properties of zinc aminophenoxy phthalocyanine-single walled carbon nanotube conjugate
- Ogbodu, Racheal O, Nyokong, Tebello
- Authors: Ogbodu, Racheal O , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7319 , http://hdl.handle.net/10962/d1020564
- Description: This work reports on the linking of zinc monoaminophenoxy (ZnMAPPc) or zinc tetraaminophenoxy phthalocyanine (ZnTAPPc) complexes to single walled carbon nanotubes (SWCNTs) through either covalent or non-covalent (adsorption) bonding. The functionalized complexes showed better thermal stability when compared to the SWCNT-COOH, ZnMAPPc and ZnTAPPc alone as confirmed by thermogravimetric analyses. The covalently linked ZnMAPc-SWCNT showed higher electron transfer rate constant and photoinduced electron efficiency when compared to adsorbed complexes. ZnMAPPc-SWCNT complexes (linked and adsorbed) showed better photophysical and photochemical properties when compared to ZnTAPPc-SWCNT complexes. The triplet, singlet oxygen and florescence quantum yields of ZnMAPPc (or ZnTAPPc) decrease upon linking or adsorption onto SWCNTs. , Original publication is available at http://dx.doi.org/10.1016/j.jphotochem.2013.09.015
- Full Text: false
- Authors: Ogbodu, Racheal O , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7319 , http://hdl.handle.net/10962/d1020564
- Description: This work reports on the linking of zinc monoaminophenoxy (ZnMAPPc) or zinc tetraaminophenoxy phthalocyanine (ZnTAPPc) complexes to single walled carbon nanotubes (SWCNTs) through either covalent or non-covalent (adsorption) bonding. The functionalized complexes showed better thermal stability when compared to the SWCNT-COOH, ZnMAPPc and ZnTAPPc alone as confirmed by thermogravimetric analyses. The covalently linked ZnMAPc-SWCNT showed higher electron transfer rate constant and photoinduced electron efficiency when compared to adsorbed complexes. ZnMAPPc-SWCNT complexes (linked and adsorbed) showed better photophysical and photochemical properties when compared to ZnTAPPc-SWCNT complexes. The triplet, singlet oxygen and florescence quantum yields of ZnMAPPc (or ZnTAPPc) decrease upon linking or adsorption onto SWCNTs. , Original publication is available at http://dx.doi.org/10.1016/j.jphotochem.2013.09.015
- Full Text: false
Effects of number of ring substituents on the physicochemical properties of zinc aminophenoxy phthalocyanine-single walled carbon nanotube conjugate
- Ogbodu, Rachael O, Nyokong, Tebello
- Authors: Ogbodu, Rachael O , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190356 , vital:44987 , xlink:href="https://doi.org/10.1016/j.jphotochem.2013.09.015"
- Description: This work reports on the linking of zinc monoaminophenoxy (ZnMAPPc) or zinc tetraaminophenoxy phthalocyanine (ZnTAPPc) complexes to single walled carbon nanotubes (SWCNTs) through either covalent or non-covalent (adsorption) bonding. The functionalized complexes showed better thermal stability when compared to the SWCNT-COOH, ZnMAPPc and ZnTAPPc alone as confirmed by thermogravimetric analyses. The covalently linked ZnMAPc-SWCNT showed higher electron transfer rate constant and photoinduced electron efficiency when compared to adsorbed complexes. ZnMAPPc-SWCNT complexes (linked and adsorbed) showed better photophysical and photochemical properties when compared to ZnTAPPc-SWCNT complexes. The triplet, singlet oxygen and florescence quantum yields of ZnMAPPc (or ZnTAPPc) decrease upon linking or adsorption onto SWCNTs.
- Full Text:
- Date Issued: 2014
- Authors: Ogbodu, Rachael O , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190356 , vital:44987 , xlink:href="https://doi.org/10.1016/j.jphotochem.2013.09.015"
- Description: This work reports on the linking of zinc monoaminophenoxy (ZnMAPPc) or zinc tetraaminophenoxy phthalocyanine (ZnTAPPc) complexes to single walled carbon nanotubes (SWCNTs) through either covalent or non-covalent (adsorption) bonding. The functionalized complexes showed better thermal stability when compared to the SWCNT-COOH, ZnMAPPc and ZnTAPPc alone as confirmed by thermogravimetric analyses. The covalently linked ZnMAPc-SWCNT showed higher electron transfer rate constant and photoinduced electron efficiency when compared to adsorbed complexes. ZnMAPPc-SWCNT complexes (linked and adsorbed) showed better photophysical and photochemical properties when compared to ZnTAPPc-SWCNT complexes. The triplet, singlet oxygen and florescence quantum yields of ZnMAPPc (or ZnTAPPc) decrease upon linking or adsorption onto SWCNTs.
- Full Text:
- Date Issued: 2014
Effects of Pluronic F127 micelles as delivering agents on the vitro dark toxicity and photodynamic therapy activity of carboxy and pyrene substituted porphyrins
- Managa, Muthumuni, Britton, Jonathan, Prinsloo, Earl, Nyokong, Tebello
- Authors: Managa, Muthumuni , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/234439 , vital:50196 , xlink:href="https://doi.org/10.1016/j.poly.2018.06.031"
- Description: Metal free, Zn and ClGa containing carboxyphenoxy and phenoxy groups (complexes 1) and pyrene groups (complexes 2) were synthesized and embedded into Pluronic F127 micelles (represented as F127). Dark toxicity and photodynamic therapy activities of the embedded porphyrins were successfully studied on MCF-7 breast cancer cells. Dark toxicity showed more than 80% cell viability for all complexes. It was found that 1-Zn + F127 showed better photodynamic therapy activity compared to 1-H2 + F127, and 1-ClGa + F127, corresponding to the high partition coefficient for the Zn porphyrin derivatives. The same applies to 2-Zn + F127 compared to 2-H2 + F127, 2-ClGa + F127. 1-ClGa and 1-Zn were also linked to Pluronic F127 silica nanoparticles. PDT activities for embedded 1-ClGa + F127 and 1-Zn + F127 were much higher than when linked to Pluronic silica nanoparticles (PluS NPs), showing the importance of loading of porphyrins into Pluronic F127 as a drug delivering agent rather than linking. PDT studies at the highest concentration of 60 µg/ml showed decrease in cell viability down to 15.9% for 2-Zn + F127. The Kp was determined in biphasic octanol and water system.
- Full Text:
- Date Issued: 2018
- Authors: Managa, Muthumuni , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/234439 , vital:50196 , xlink:href="https://doi.org/10.1016/j.poly.2018.06.031"
- Description: Metal free, Zn and ClGa containing carboxyphenoxy and phenoxy groups (complexes 1) and pyrene groups (complexes 2) were synthesized and embedded into Pluronic F127 micelles (represented as F127). Dark toxicity and photodynamic therapy activities of the embedded porphyrins were successfully studied on MCF-7 breast cancer cells. Dark toxicity showed more than 80% cell viability for all complexes. It was found that 1-Zn + F127 showed better photodynamic therapy activity compared to 1-H2 + F127, and 1-ClGa + F127, corresponding to the high partition coefficient for the Zn porphyrin derivatives. The same applies to 2-Zn + F127 compared to 2-H2 + F127, 2-ClGa + F127. 1-ClGa and 1-Zn were also linked to Pluronic F127 silica nanoparticles. PDT activities for embedded 1-ClGa + F127 and 1-Zn + F127 were much higher than when linked to Pluronic silica nanoparticles (PluS NPs), showing the importance of loading of porphyrins into Pluronic F127 as a drug delivering agent rather than linking. PDT studies at the highest concentration of 60 µg/ml showed decrease in cell viability down to 15.9% for 2-Zn + F127. The Kp was determined in biphasic octanol and water system.
- Full Text:
- Date Issued: 2018
Effects of pluronic silica nanoparticles on the photophysical and photodynamic therapy behavior of triphenyl-p-phenoxy benzoic acid metalloporphyrins
- Managa, Muthumuni, Britton, Jonathan, Prinsloo, Earl, Nyokong, Tebello
- Authors: Managa, Muthumuni , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239698 , vital:50756 , xlink:href="https://doi.org/10.1080/00958972.2016.1236372"
- Description: 5, 10, 15, Triphenyl-20-p-phenoxy benzoic acid porphyrins (P) containing Zn (ZnP), Ga (GaP), and Si (SiP) were synthesized and conjugated to pluronic-silica (PluS) nanoparticles (NPs) where the fluorescence and singlet oxygen generating behavior of the porphyrins were investigated. The highest singlet oxygen quantum yield (ΦΔ) was obtained for ZnP. When the porphyrins were conjugated to the PluS NPs, the ΦΔ was quenched and fluorescence was enhanced. The pore size of the NPs upon conjugation decreased from 18.9 nm for PluS NPs to 2.4 nm (for ZnP as an example) as determined by applying the Brunauer–Emmett–Teller method. The porphyrin complexes and their conjugates were tested for their photodynamic therapy (PDT) activity on MCF-7 breast cancer cells. It was found that ZnP and its conjugate showed the highest PDT activity. The p > 0.05 indicated that ZnP is significantly different than GaP and SiP.
- Full Text:
- Date Issued: 2016
- Authors: Managa, Muthumuni , Britton, Jonathan , Prinsloo, Earl , Nyokong, Tebello
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/239698 , vital:50756 , xlink:href="https://doi.org/10.1080/00958972.2016.1236372"
- Description: 5, 10, 15, Triphenyl-20-p-phenoxy benzoic acid porphyrins (P) containing Zn (ZnP), Ga (GaP), and Si (SiP) were synthesized and conjugated to pluronic-silica (PluS) nanoparticles (NPs) where the fluorescence and singlet oxygen generating behavior of the porphyrins were investigated. The highest singlet oxygen quantum yield (ΦΔ) was obtained for ZnP. When the porphyrins were conjugated to the PluS NPs, the ΦΔ was quenched and fluorescence was enhanced. The pore size of the NPs upon conjugation decreased from 18.9 nm for PluS NPs to 2.4 nm (for ZnP as an example) as determined by applying the Brunauer–Emmett–Teller method. The porphyrin complexes and their conjugates were tested for their photodynamic therapy (PDT) activity on MCF-7 breast cancer cells. It was found that ZnP and its conjugate showed the highest PDT activity. The p > 0.05 indicated that ZnP is significantly different than GaP and SiP.
- Full Text:
- Date Issued: 2016
Effects of pyrene on the photophysical and two-photon absorption-based nonlinear optical properties of indium (III) phthalocyanines
- Sanusi, Kayode, Nyokong, Tebello
- Authors: Sanusi, Kayode , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189957 , vital:44951 , xlink:href="https://doi.org/10.1080/00958972.2014.959509"
- Description: Photophysical and two-photon-dependent nonlinear absorption properties of two chloroindium(III) phthalocyanines bearing pyrene units have been investigated. The tetra- (3) and the tri- (4) pyrene-substituted phthalocyanines exhibit strong triplet absorption with high triplet yields ( ) of 0.79 and 0.83, respectively. The measured nonlinear optical data, such as the two photon absorption cross-sections, the third- and second-order nonlinearities were found to be comparable with those of literature, thus, making the compounds promising candidates for a broad range of nonlinear optical applications.
- Full Text:
- Date Issued: 2014
- Authors: Sanusi, Kayode , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189957 , vital:44951 , xlink:href="https://doi.org/10.1080/00958972.2014.959509"
- Description: Photophysical and two-photon-dependent nonlinear absorption properties of two chloroindium(III) phthalocyanines bearing pyrene units have been investigated. The tetra- (3) and the tri- (4) pyrene-substituted phthalocyanines exhibit strong triplet absorption with high triplet yields ( ) of 0.79 and 0.83, respectively. The measured nonlinear optical data, such as the two photon absorption cross-sections, the third- and second-order nonlinearities were found to be comparable with those of literature, thus, making the compounds promising candidates for a broad range of nonlinear optical applications.
- Full Text:
- Date Issued: 2014
Effects of pyrene on the photophysical and two-photon absorption-based nonlinear optical properties of indium(III) phthalocyanines
- Sanusi, Kayode, Nyokong, Tebello
- Authors: Sanusi, Kayode , Nyokong, Tebello
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:7314 , http://hdl.handle.net/10962/d1020540
- Description: Photophysical and two-photon-dependent nonlinear absorption properties of two chloroindium(III) phthalocyanines bearing pyrene units have been investigated. The tetra- (3) and the tri- (4) pyrene-substituted phthalocyanines exhibit strong triplet absorption with high triplet yields () of 0.79 and 0.83, respectively. The measured nonlinear optical data, such as the two photon absorption cross-sections, the third- and second-order nonlinearities were found to be comparable with those of literature, thus, making the compounds promising candidates for a broad range of nonlinear optical applications. , Original publication is available at http://dx.doi.org/10.1080/00958972.2014.959509
- Full Text: false
- Date Issued: 2014
- Authors: Sanusi, Kayode , Nyokong, Tebello
- Date: 2014
- Language: English
- Type: Article
- Identifier: vital:7314 , http://hdl.handle.net/10962/d1020540
- Description: Photophysical and two-photon-dependent nonlinear absorption properties of two chloroindium(III) phthalocyanines bearing pyrene units have been investigated. The tetra- (3) and the tri- (4) pyrene-substituted phthalocyanines exhibit strong triplet absorption with high triplet yields () of 0.79 and 0.83, respectively. The measured nonlinear optical data, such as the two photon absorption cross-sections, the third- and second-order nonlinearities were found to be comparable with those of literature, thus, making the compounds promising candidates for a broad range of nonlinear optical applications. , Original publication is available at http://dx.doi.org/10.1080/00958972.2014.959509
- Full Text: false
- Date Issued: 2014
Effects of redox mediators on the catalytic activity of iron porphyrins towards oxygen reduction in acidic media
- He, Qinggang, Wu, Gang, Liu, Ke, Khene, Samson M, Li, Qing, Mugadza, Tawanda, Deunf, Elise, Nyokong, Tebello, Chen, Shaowei W
- Authors: He, Qinggang , Wu, Gang , Liu, Ke , Khene, Samson M , Li, Qing , Mugadza, Tawanda , Deunf, Elise , Nyokong, Tebello , Chen, Shaowei W
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241472 , vital:50942 , xlink:href="https://doi.org/10.1002/celc.201402054"
- Description: The effects of different redox mediators on the oxygen reduction reaction (ORR) catalyzed by an iron porphyrin complex, iron(III) meso-tetra(N-methyl-4-pyridyl)porphine chloride [FeIIITMPyP], in 0.1 M triflic acid were investigated by cyclic voltammetry (CV) and spectroelectrochemistry in conjunction with density functional theory (DFT) calculations. The formal potentials of the FeIIITMPyP catalyst and the redox mediators, as well as the half-wave potentials for the ORR, were determined by CV in the absence and presence of oxygen in acidic solutions. UV/Vis spectroscopic and spectroelectrochemical studies confirmed that only the 2,2′-azino-bis(3-ethylbenzothiazioline-6-sulfonic acid)diammonium salt (C18H24N6O6S4) showed effective interactions with FeIIITMPyP during the ORR. DFT calculations suggested strong interaction between FeIIITMPyP and the C18H24N6O6S4 redox mediator. The redox mediator caused lengthening of the dioxygen iron bond, which thus suggested easier dioxygen reduction. Consistent results were observed in electrochemical impedance spectroscopic measurements for which the electron-transfer kinetics were also evaluated.
- Full Text:
- Date Issued: 2014
- Authors: He, Qinggang , Wu, Gang , Liu, Ke , Khene, Samson M , Li, Qing , Mugadza, Tawanda , Deunf, Elise , Nyokong, Tebello , Chen, Shaowei W
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241472 , vital:50942 , xlink:href="https://doi.org/10.1002/celc.201402054"
- Description: The effects of different redox mediators on the oxygen reduction reaction (ORR) catalyzed by an iron porphyrin complex, iron(III) meso-tetra(N-methyl-4-pyridyl)porphine chloride [FeIIITMPyP], in 0.1 M triflic acid were investigated by cyclic voltammetry (CV) and spectroelectrochemistry in conjunction with density functional theory (DFT) calculations. The formal potentials of the FeIIITMPyP catalyst and the redox mediators, as well as the half-wave potentials for the ORR, were determined by CV in the absence and presence of oxygen in acidic solutions. UV/Vis spectroscopic and spectroelectrochemical studies confirmed that only the 2,2′-azino-bis(3-ethylbenzothiazioline-6-sulfonic acid)diammonium salt (C18H24N6O6S4) showed effective interactions with FeIIITMPyP during the ORR. DFT calculations suggested strong interaction between FeIIITMPyP and the C18H24N6O6S4 redox mediator. The redox mediator caused lengthening of the dioxygen iron bond, which thus suggested easier dioxygen reduction. Consistent results were observed in electrochemical impedance spectroscopic measurements for which the electron-transfer kinetics were also evaluated.
- Full Text:
- Date Issued: 2014
Effects of Redox Mediators on the Catalytic Activity of Iron Porphyrins towards Oxygen Reduction in Acidic Media
- He, Qinggang, Wu, Gang, Liu, Ke, Khene, M Samson, Li, Qing, Mugadza, Tawanda, Deunf, Elise, Nyokong, Tebello, Chen, Shaowei W
- Authors: He, Qinggang , Wu, Gang , Liu, Ke , Khene, M Samson , Li, Qing , Mugadza, Tawanda , Deunf, Elise , Nyokong, Tebello , Chen, Shaowei W
- Language: English
- Type: Article
- Identifier: vital:7291 , http://hdl.handle.net/10962/d1020354
- Description: The effects of different redox mediators on the oxygen reduction reaction (ORR) catalyzed by an iron porphyrin complex, iron(III) meso-tetra(N-methyl-4-pyridyl)porphine chloride [FeIIITMPyP], in 0.1 M triflic acid were investigated by cyclic voltammetry (CV) and spectroelectrochemistry in conjunction with density functional theory (DFT) calculations. The formal potentials of the FeIIITMPyP catalyst and the redox mediators, as well as the half-wave potentials for the ORR, were determined by CV in the absence and presence of oxygen in acidic solutions. UV/Vis spectroscopic and spectroelectrochemical studies confirmed that only the 2,2′-azino-bis(3-ethylbenzothiazioline-6-sulfonic acid)diammonium salt (C18H24N6O6S4) showed effective interactions with FeIIITMPyP during the ORR. DFT calculations suggested strong interaction between FeIIITMPyP and the C18H24N6O6S4 redox mediator. The redox mediator caused lengthening of the dioxygen iron bond, which thus suggested easier dioxygen reduction. Consistent results were observed in electrochemical impedance spectroscopic measurements for which the electron-transfer kinetics were also evaluated. , Original publication is available at http://dx.doi.org/10.1002/celc.201402054
- Full Text: false
- Authors: He, Qinggang , Wu, Gang , Liu, Ke , Khene, M Samson , Li, Qing , Mugadza, Tawanda , Deunf, Elise , Nyokong, Tebello , Chen, Shaowei W
- Language: English
- Type: Article
- Identifier: vital:7291 , http://hdl.handle.net/10962/d1020354
- Description: The effects of different redox mediators on the oxygen reduction reaction (ORR) catalyzed by an iron porphyrin complex, iron(III) meso-tetra(N-methyl-4-pyridyl)porphine chloride [FeIIITMPyP], in 0.1 M triflic acid were investigated by cyclic voltammetry (CV) and spectroelectrochemistry in conjunction with density functional theory (DFT) calculations. The formal potentials of the FeIIITMPyP catalyst and the redox mediators, as well as the half-wave potentials for the ORR, were determined by CV in the absence and presence of oxygen in acidic solutions. UV/Vis spectroscopic and spectroelectrochemical studies confirmed that only the 2,2′-azino-bis(3-ethylbenzothiazioline-6-sulfonic acid)diammonium salt (C18H24N6O6S4) showed effective interactions with FeIIITMPyP during the ORR. DFT calculations suggested strong interaction between FeIIITMPyP and the C18H24N6O6S4 redox mediator. The redox mediator caused lengthening of the dioxygen iron bond, which thus suggested easier dioxygen reduction. Consistent results were observed in electrochemical impedance spectroscopic measurements for which the electron-transfer kinetics were also evaluated. , Original publication is available at http://dx.doi.org/10.1002/celc.201402054
- Full Text: false
Effects of ring substituents on electrocatalytic activity of manganese phthalocyanines towards the reduction of molecular oxygen
- Sehlotho, Nthapo, Nyokong, Tebello
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6594 , http://hdl.handle.net/10962/d1004343
- Description: Reduction of oxygen electrocatalyzed by adsorbed films of manganese phthalocyanine complexes is reported. The complexes studied were: manganese phthalocyanine (MnPc, 1); manganese tetraamino phthalocyanine (MnTAPc, 2); manganese tetrapentoxy pyrrole phthalocyanine (MnTPePyrPc, 3); manganese tetra phenoxy pyrrole phthalocyanine (MnTPPyrPc, 4); manganese tetra mercaptopyrimidine phthalocyanine (MnTMPyPc, 5) and manganese tetra ethoxy thiophene phthalocyanine (MnTETPc, 6). The reaction was conducted in buffer solutions of pH range 1–12. Rotating disk electrode voltammetry revealed two electron reduction in acidic and slightly alkaline media due to the formation of hydrogen peroxide. In highly basic media, water is the major product formed via four electron transfer. The reaction was found to be first order in the diffusing analyte oxygen.
- Full Text:
- Date Issued: 2006
- Authors: Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2006
- Language: English
- Type: Article
- Identifier: vital:6594 , http://hdl.handle.net/10962/d1004343
- Description: Reduction of oxygen electrocatalyzed by adsorbed films of manganese phthalocyanine complexes is reported. The complexes studied were: manganese phthalocyanine (MnPc, 1); manganese tetraamino phthalocyanine (MnTAPc, 2); manganese tetrapentoxy pyrrole phthalocyanine (MnTPePyrPc, 3); manganese tetra phenoxy pyrrole phthalocyanine (MnTPPyrPc, 4); manganese tetra mercaptopyrimidine phthalocyanine (MnTMPyPc, 5) and manganese tetra ethoxy thiophene phthalocyanine (MnTETPc, 6). The reaction was conducted in buffer solutions of pH range 1–12. Rotating disk electrode voltammetry revealed two electron reduction in acidic and slightly alkaline media due to the formation of hydrogen peroxide. In highly basic media, water is the major product formed via four electron transfer. The reaction was found to be first order in the diffusing analyte oxygen.
- Full Text:
- Date Issued: 2006
Effects of substituents and solvents on the photochemical properties of zinc phthalocyanine complexes and their protonated derivatives
- Ogunsipe, Abimbola Olukayode, Nyokong, Tebello
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004
- Authors: Ogunsipe, Abimbola Olukayode , Nyokong, Tebello
- Date: 2004
- Language: English
- Type: Article
- Identifier: vital:6585 , http://hdl.handle.net/10962/d1004161
- Description: Zinc phthalocyanine derivatives containing various ring substituents and axial ligands were studied with respect to the effect of substituents on protonation. Aggregation resulted in failure of some of the ZnPc derivatives to protonate. In fact addition of protonating agents to aggregated ZnPc derivatives resulted in increase in aggregation followed by slow degradation. Axial ligands were lost on protonation. Photobleaching, fluorescence and singlet oxygen quantum yields of the protonated derivatives were compared with those of the unprotonated derivatives. In all cases protonation decreases the singlet oxygen and fluorescence quantum yields. However, photobleaching quantum yields decreased (i.e. stability increased) for the protonated derivatives except when axial ligands were present, where protonation resulted in decrease in stability.
- Full Text:
- Date Issued: 2004
Effects of substituents on the electrocatalytic activity of cobalt phthalocyanines when conjugated to graphene quantum dots
- Centane, Sixolile, Achadu, Ojodomo John, Nyokong, Tebello
- Authors: Centane, Sixolile , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188237 , vital:44737 , xlink:href="https://doi.org/10.1002/elan.201700252"
- Description: We report on the π–π interactions between graphene quantum dots (GQDs) and the following cobalt phthalocyanine derivatives: cobalt monocarboxyphenoxy phthalocyanine (complex 1), cobalt tetracarboxyphenoxyphthalocyanine (complex 2), and cobalt tetraaminophenoxy phthalocyanine (complex 3). The conjugates (conj) with GQDs are represented as 1@GQDs(conj), 2@GQDs(conj) and 3@GQDs(conj), respectively. The resulting phthalocyanine/GQDs conjugates were adsorbed on containing a glassy carbon electrode (GCE) using the drop and dry method. We explore the electrochemical properties of phthalocyanines functionalized with both electron withdrawing groups and electron donating groups when non-covalently linked to the π-electron rich graphene quantum dots. GCE/3, GCE/2@GQDs(conj) and GCE/1@GQDs(conj) had the lowest limits of detection (LOD). Sequentially modified electrodes showed less favourable detection limits compared to the conjugates.
- Full Text:
- Date Issued: 2017
- Authors: Centane, Sixolile , Achadu, Ojodomo John , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188237 , vital:44737 , xlink:href="https://doi.org/10.1002/elan.201700252"
- Description: We report on the π–π interactions between graphene quantum dots (GQDs) and the following cobalt phthalocyanine derivatives: cobalt monocarboxyphenoxy phthalocyanine (complex 1), cobalt tetracarboxyphenoxyphthalocyanine (complex 2), and cobalt tetraaminophenoxy phthalocyanine (complex 3). The conjugates (conj) with GQDs are represented as 1@GQDs(conj), 2@GQDs(conj) and 3@GQDs(conj), respectively. The resulting phthalocyanine/GQDs conjugates were adsorbed on containing a glassy carbon electrode (GCE) using the drop and dry method. We explore the electrochemical properties of phthalocyanines functionalized with both electron withdrawing groups and electron donating groups when non-covalently linked to the π-electron rich graphene quantum dots. GCE/3, GCE/2@GQDs(conj) and GCE/1@GQDs(conj) had the lowest limits of detection (LOD). Sequentially modified electrodes showed less favourable detection limits compared to the conjugates.
- Full Text:
- Date Issued: 2017
Effects of substituents on the photochemical and photophysical properties of main group metal phthalocyanines
- Authors: Nyokong, Tebello
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6581 , http://hdl.handle.net/10962/d1004146
- Description: The review focuses on the photochemical (singlet oxygen and photobleaching quantum yields) and photophysical (triplet quantum yields and lifetimes and fluorescence lifetimes) properties of metallophthalocyanine complexes containing main group metals (Zn, Al, Ge, Si, Sn, Ga and In) and some unmetallated phthalocyanine complexes. Five tables containing photophysical and photochemical data for sulfonated phthalocyanines, tetra-, octa-substituted and unsubstituted phthalocyanines in a variety of solvents, are included in the review.
- Full Text:
- Date Issued: 2007
- Authors: Nyokong, Tebello
- Date: 2007
- Language: English
- Type: Article
- Identifier: vital:6581 , http://hdl.handle.net/10962/d1004146
- Description: The review focuses on the photochemical (singlet oxygen and photobleaching quantum yields) and photophysical (triplet quantum yields and lifetimes and fluorescence lifetimes) properties of metallophthalocyanine complexes containing main group metals (Zn, Al, Ge, Si, Sn, Ga and In) and some unmetallated phthalocyanine complexes. Five tables containing photophysical and photochemical data for sulfonated phthalocyanines, tetra-, octa-substituted and unsubstituted phthalocyanines in a variety of solvents, are included in the review.
- Full Text:
- Date Issued: 2007
Effects of symmetry and the number of positive charges on the photocatalytic activity of indium phthalocyanines when embedded in electrospun fibers
- Chakona, Gamuchirai, Nyokong, Tebello
- Authors: Chakona, Gamuchirai , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188304 , vital:44743 , xlink:href="https://doi.org/10.1016/j.ica.2016.12.025"
- Description: Photooxidations of bisphenol A and 4-chlorophenol were carried out in this study using two asymmetric indium(III) phthalocyanines photosensitizers: the first consisting of one quaternized 4-pyridyloxyl and no other substituents (complex 1) and the second containing three quaternized 4-pyridylsulfanyl units and one aminophenoxy (complex 3). The asymmetry of complex 3 is additionally caused by the presence of two linking atoms (O and S). The symmetrically substituted indium(III) phthalocyanine containing four quaternized 4-pyridyloxyl units (complex 2) was also studied. The complexes were embedded in electrospun polystyrene fiber for heterogeneous photocatalytic transformation of 4-chlorophenol and bisphenol A. When immobilized on electrospun fibers, complexes 1, 2 and 3 gave singlet oxygen values of 0.31, 0.39 and 0.50 in water, respectively. Complex 3 showed the best photocatalytic behavior with observed rate constants of 2.8 × 10−3 min−1 for bisphenol A and 3.8 × 10−3 min−1 for 4-chlorophenol.
- Full Text:
- Date Issued: 2017
- Authors: Chakona, Gamuchirai , Nyokong, Tebello
- Date: 2017
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/188304 , vital:44743 , xlink:href="https://doi.org/10.1016/j.ica.2016.12.025"
- Description: Photooxidations of bisphenol A and 4-chlorophenol were carried out in this study using two asymmetric indium(III) phthalocyanines photosensitizers: the first consisting of one quaternized 4-pyridyloxyl and no other substituents (complex 1) and the second containing three quaternized 4-pyridylsulfanyl units and one aminophenoxy (complex 3). The asymmetry of complex 3 is additionally caused by the presence of two linking atoms (O and S). The symmetrically substituted indium(III) phthalocyanine containing four quaternized 4-pyridyloxyl units (complex 2) was also studied. The complexes were embedded in electrospun polystyrene fiber for heterogeneous photocatalytic transformation of 4-chlorophenol and bisphenol A. When immobilized on electrospun fibers, complexes 1, 2 and 3 gave singlet oxygen values of 0.31, 0.39 and 0.50 in water, respectively. Complex 3 showed the best photocatalytic behavior with observed rate constants of 2.8 × 10−3 min−1 for bisphenol A and 3.8 × 10−3 min−1 for 4-chlorophenol.
- Full Text:
- Date Issued: 2017
Effects of the carboxylic acid substituents on the photophysical and nonlinear optical properties of asymmetrical Zn (II) phthalocyanines–quantum dots conjugates
- Mgidlana, Sithi, Oluwole, David O, Nyokong, Tebello
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187662 , vital:44684 , xlink:href="https://doi.org/10.1080/24701556.2018.1503684"
- Description: This work reports on three asymmetrical Zn(II) phthalocyanines, namely: zinc(II) 3–(4-phenoxy)propanoic acid) phthalocyanine(1), zinc(II) 3–(4-phenoxy carboxylic acid) phthalocyanine (2) and zinc(II) 3–(4–oxy)phenoxy)acetic acid phthalocyanine (3) when covalently linked to glutathione(GSH) capped CdTe/ZnSe and CdTe/ZnSe/ZnO quantum dots (QDs). Of the Pc complexes alone, 1 afforded the highest triplet quantum yield (ΦT) value of 0.67 with corresponding largest nonlinear absorption coefficient (βeff) value of 14.0 cm/GW compared to 2 and 3. The conjugates afforded improved triplet quantum yield and nonlinear optical behavior in comparison to the Pc complexes alone.
- Full Text:
- Date Issued: 2018
- Authors: Mgidlana, Sithi , Oluwole, David O , Nyokong, Tebello
- Date: 2018
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/187662 , vital:44684 , xlink:href="https://doi.org/10.1080/24701556.2018.1503684"
- Description: This work reports on three asymmetrical Zn(II) phthalocyanines, namely: zinc(II) 3–(4-phenoxy)propanoic acid) phthalocyanine(1), zinc(II) 3–(4-phenoxy carboxylic acid) phthalocyanine (2) and zinc(II) 3–(4–oxy)phenoxy)acetic acid phthalocyanine (3) when covalently linked to glutathione(GSH) capped CdTe/ZnSe and CdTe/ZnSe/ZnO quantum dots (QDs). Of the Pc complexes alone, 1 afforded the highest triplet quantum yield (ΦT) value of 0.67 with corresponding largest nonlinear absorption coefficient (βeff) value of 14.0 cm/GW compared to 2 and 3. The conjugates afforded improved triplet quantum yield and nonlinear optical behavior in comparison to the Pc complexes alone.
- Full Text:
- Date Issued: 2018
Effects of the number of ring substituents of cobalt carboxyphthalocyanines on the electrocatalytic detection of nitrite, cysteine and melatonin
- Matemadombo, Fungisai, Sehlotho, Nthapo, Nyokong, Tebello
- Authors: Matemadombo, Fungisai , Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263408 , vital:53625 , xlink:href="https://doi.org/10.1142/S108842460900125X"
- Description: Cobalt phthalocyanine (CoPc), cobalt tetracarboxy phthalocyanine (CoTCPc) and cobalt octacarboxy phthalocyanine (CoOCPc), adsorbed onto glassy carbon electrodes, have been used for the electrocatalytic detection of nitrite, L-cysteine and melatonin. The modified electrodes electrocatalytically detected nitrite around 800 mV vs.Ag|AgCl, a value less positive compared to that of an unmodified glassy carbon electrode (at 950 mV vs.Ag|AgCl) and also gave detection limits in the 10-7 M range for nitrite detection. L-cysteine was detected by the modified electrodes at potentials between 0.50 to 0.65 V vs.Ag|AgCl, with L-cysteine detection limits also in the 10-7 M range. The detection limits for melatonin ranged from 10-7 to 10-6 M. CoPc-modified electrodes displayed good separation of interferents (tryptophan and ascorbic acid) in the presence of melatonin. Analyses of commercial melatonin tablets using modified electrodes gave excellent agreement with manufacturer's value for all modified electrodes of this work.
- Full Text:
- Date Issued: 2009
- Authors: Matemadombo, Fungisai , Sehlotho, Nthapo , Nyokong, Tebello
- Date: 2009
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/263408 , vital:53625 , xlink:href="https://doi.org/10.1142/S108842460900125X"
- Description: Cobalt phthalocyanine (CoPc), cobalt tetracarboxy phthalocyanine (CoTCPc) and cobalt octacarboxy phthalocyanine (CoOCPc), adsorbed onto glassy carbon electrodes, have been used for the electrocatalytic detection of nitrite, L-cysteine and melatonin. The modified electrodes electrocatalytically detected nitrite around 800 mV vs.Ag|AgCl, a value less positive compared to that of an unmodified glassy carbon electrode (at 950 mV vs.Ag|AgCl) and also gave detection limits in the 10-7 M range for nitrite detection. L-cysteine was detected by the modified electrodes at potentials between 0.50 to 0.65 V vs.Ag|AgCl, with L-cysteine detection limits also in the 10-7 M range. The detection limits for melatonin ranged from 10-7 to 10-6 M. CoPc-modified electrodes displayed good separation of interferents (tryptophan and ascorbic acid) in the presence of melatonin. Analyses of commercial melatonin tablets using modified electrodes gave excellent agreement with manufacturer's value for all modified electrodes of this work.
- Full Text:
- Date Issued: 2009
Effects of ZnO nanohexagons and nanorods on the fluorescence behavior of metallophthalocyanines
- D’Souza, Sarah, Moeno, Sharon, Nyokong, Tebello
- Authors: D’Souza, Sarah , Moeno, Sharon , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7263 , http://hdl.handle.net/10962/d1020272
- Description: This paper looks at the fluorescence behavior of zinc phthalocyanines: 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptoacetic acid phthalocyaninato) zinc(II) (ZnTMAAPc), 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptopropanoic acid phthalocyaninato) zinc(II) (ZnTMPAPc) and (OH)AlPcSmix (the latter contains a mixture of the di-, tri- and tetra-sulfonated derivatives with an average of three sulfonated groups per molecule) in the presence of ZnO nanoparticles. Fluorescence lifetimes of Pc complexes generally decreased in the presence of ZnO nanoparticles, with generally longer lifetimes for ZnO nanohexagons compared to ZnO nanorods. , Original publication is available at http://dx.doi.org/10.1016/j.poly.2014.09.012
- Full Text: false
- Authors: D’Souza, Sarah , Moeno, Sharon , Nyokong, Tebello
- Language: English
- Type: Article
- Identifier: vital:7263 , http://hdl.handle.net/10962/d1020272
- Description: This paper looks at the fluorescence behavior of zinc phthalocyanines: 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptoacetic acid phthalocyaninato) zinc(II) (ZnTMAAPc), 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptopropanoic acid phthalocyaninato) zinc(II) (ZnTMPAPc) and (OH)AlPcSmix (the latter contains a mixture of the di-, tri- and tetra-sulfonated derivatives with an average of three sulfonated groups per molecule) in the presence of ZnO nanoparticles. Fluorescence lifetimes of Pc complexes generally decreased in the presence of ZnO nanoparticles, with generally longer lifetimes for ZnO nanohexagons compared to ZnO nanorods. , Original publication is available at http://dx.doi.org/10.1016/j.poly.2014.09.012
- Full Text: false
Effects of ZnO nanohexagons and nanorods on the fluorescence behavior of metallophthalocyanines
- D'Souza, Sarah, Moeno, Sharon, Nyokong, Tebello
- Authors: D'Souza, Sarah , Moeno, Sharon , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189741 , vital:44927 , xlink:href="https://doi.org/10.1016/j.poly.2014.09.012"
- Description: This paper looks at the fluorescence behavior of zinc phthalocyanines: 2,(3),9(10),16(17),23(24)-tetrakis- (mercaptoacetic acid phthalocyaninato) zinc(II) (ZnTMAAPc), 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptopropanoic acid phthalocyaninato) zinc(II) (ZnTMPAPc) and (OH)AlPcSmix (the latter contains a mixture of the di-, tri- and tetra-sulfonated derivatives with an average of three sulfonated groups per molecule) in the presence of ZnO nanoparticles. Fluorescence lifetimes of Pc complexes generally decreased in the presence of ZnO nanoparticles, with generally longer lifetimes for ZnO nanohexagons compared to ZnO nanorods.
- Full Text:
- Date Issued: 2015
- Authors: D'Souza, Sarah , Moeno, Sharon , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189741 , vital:44927 , xlink:href="https://doi.org/10.1016/j.poly.2014.09.012"
- Description: This paper looks at the fluorescence behavior of zinc phthalocyanines: 2,(3),9(10),16(17),23(24)-tetrakis- (mercaptoacetic acid phthalocyaninato) zinc(II) (ZnTMAAPc), 2,(3),9(10),16(17),23(24)-tetrakis-(mercaptopropanoic acid phthalocyaninato) zinc(II) (ZnTMPAPc) and (OH)AlPcSmix (the latter contains a mixture of the di-, tri- and tetra-sulfonated derivatives with an average of three sulfonated groups per molecule) in the presence of ZnO nanoparticles. Fluorescence lifetimes of Pc complexes generally decreased in the presence of ZnO nanoparticles, with generally longer lifetimes for ZnO nanohexagons compared to ZnO nanorods.
- Full Text:
- Date Issued: 2015
Efficient energy transfer in ethynyl bridged corrole–BODIPY dyads
- Yan, Yu, Wu, Fan, Qin, Jiawei, Xu, Haijun, Shi, Maohu, Zhou, Jingfeng, Mack, John, Fomo, Gertrude, Nyokong, Tebello, Shen, Zhen
- Authors: Yan, Yu , Wu, Fan , Qin, Jiawei , Xu, Haijun , Shi, Maohu , Zhou, Jingfeng , Mack, John , Fomo, Gertrude , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240899 , vital:50883 , xlink:href="https://doi.org/10.1039/C6RA12271J"
- Description: A series of new corrole–BODIPY dyads bridged by ethynyl linker moieties have been synthesized in high yields and fully characterized. The direction of energy transfer upon electronic excitation has been explored, and was found to be dependent on the number of corrole rings and their connection position on the BODIPY core. Intense bands in the absorption spectrum cover most of the visible region, which is potentially advantageous for capturing solar energy. Studies on the excitation spectra and lifetimes suggest that the energy transfer efficiency between the BODIPY and corrole moieties reaches almost 85%, which appears to be efficient in the context of energy transfer within the singlet manifold.
- Full Text:
- Date Issued: 2016
- Authors: Yan, Yu , Wu, Fan , Qin, Jiawei , Xu, Haijun , Shi, Maohu , Zhou, Jingfeng , Mack, John , Fomo, Gertrude , Nyokong, Tebello , Shen, Zhen
- Date: 2016
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/240899 , vital:50883 , xlink:href="https://doi.org/10.1039/C6RA12271J"
- Description: A series of new corrole–BODIPY dyads bridged by ethynyl linker moieties have been synthesized in high yields and fully characterized. The direction of energy transfer upon electronic excitation has been explored, and was found to be dependent on the number of corrole rings and their connection position on the BODIPY core. Intense bands in the absorption spectrum cover most of the visible region, which is potentially advantageous for capturing solar energy. Studies on the excitation spectra and lifetimes suggest that the energy transfer efficiency between the BODIPY and corrole moieties reaches almost 85%, which appears to be efficient in the context of energy transfer within the singlet manifold.
- Full Text:
- Date Issued: 2016