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Gold corroles are not readily accessible and they display no interesting physical or chemical properties. A facile methodology has now been developed for obtaining selectively CF3-substituted gold(III) corroles and the introduction of these groups has been found to have an immense effect on the structures of the complexes, their photophysical and redox properties, and on their ability to participate in catalytic processes. [ABSTRACT FROM AUTHOR]

Closely positioned donor-acceptor pairs facilitate electron- and energy-transfer events, relevant to light energy conversion. Here, a triad system TPACor-C60, possessing a free-base corrole as central unit that linked the energy donor triphenylamine (TPA) at the meso position and an electron acceptor fullerene (C60) at the b-pyrrole position was newly synthesized, as were the component dyads TPACor and Cor-C60. Spectroscopic, electrochemical, and DFT studies confirmed the molecular integrity and existence of a moderate level of intramolecular interactions between the components. Steady-state fluorescence studies showed efficient energy transfer from 1TPA* to the corrole and subsequent electron transfer from 1corrole* to fullerene. Further studies involving femtosecond and nanosecond laser flash photolysis confirmed electron transfer to be the quenching mechanism of corrole emission, in which the electron-transfer products, the corrole radical cation (Cor·+ in Cor-C60 and TPA-Cor·+ in TPACor-C60) and fullerene radical anion (C60 ·-), could be spectrally characterized. Owing to the close proximity of the donor and acceptor entities in the dyad and triad, the rate of charge separation, kCS, was found to be about 1011 s-1, suggesting the occurrence of an ultrafast charge-separation process. Interestingly, although an order of magnitude slower than kCS, the rate of charge recombination, kCR, was also found to be rapid (kCR ≈1010 s-1), and both processes followed the solvent polarity trend DMF>benzonitrile> THF>toluene. The charge-separated species relaxed directly to the ground state in polar solvents while in toluene, formation of 3corrole* was observed, thus implying that the energy of the charge-separated state in a nonpolar solvent is higher than the energy of 3corrole* being about 1.52 eV. That is, ultrafast formation of a high-energy chargeseparated state in toluene has been achieved in these closely spaced corrole-fullerene donor-acceptor conjugates. [ABSTRACT FROM AUTHOR]

New corrole sensitizers having a triphenylamine moiety at the - meso position and a carboxylic anchoring group at the pyrrole-β position, in both free-base and copper complex forms, have been designed, synthesized, and tried as sensitizers in dye-sensitized solar cells. All the substituted carboxy-corroles were completely characterized from structural, optical and electrochemical points of view. Computational investigations by means of density functional theory (DFT) and time-dependent-DFT (TD-DFT) calculations have been carried out, in order to give a deep insight into the charge-injection process. Quite low photovoltaic performances were obtained, particularly for the investigated copper complexes, possibly due to an unfavorable energy-level alignment between the dye's injecting states and TiO2 conduction band, limiting the charge injection and thus the photocurrent extracted from the devices. Our study may provide the guidelines for future development of more efficient solar-cell sensitizers. Scheme of a dye-sensitized solar cell (DSC) based on a triphenylamine-corrole dye and a I-/I3- electrolyte. [ABSTRACT FROM AUTHOR]

Gold corroles are not readily accessible and they display no interesting physical or chemical properties. A facile methodology has now been developed for obtaining selectively CF 3 -substituted gold(III) corroles and the introduction of these groups has been found to have an immense effect on the structures of the complexes, their photophysical and redox properties, and on their ability to participate in catalytic processes., (© 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Closely positioned donor-acceptor pairs facilitate electron- and energy-transfer events, relevant to light energy conversion. Here, a triad system TPACor-C60 , possessing a free-base corrole as central unit that linked the energy donor triphenylamine (TPA) at the meso position and an electron acceptor fullerene (C60) at the β-pyrrole position was newly synthesized, as were the component dyads TPA-Cor and Cor-C60. Spectroscopic, electrochemical, and DFT studies confirmed the molecular integrity and existence of a moderate level of intramolecular interactions between the components. Steady-state fluorescence studies showed efficient energy transfer from (1) TPA* to the corrole and subsequent electron transfer from (1) corrole* to fullerene. Further studies involving femtosecond and nanosecond laser flash photolysis confirmed electron transfer to be the quenching mechanism of corrole emission, in which the electron-transfer products, the corrole radical cation (Cor(⋅+) in Cor-C60 and TPA-Cor(⋅+) in TPACor-C60) and fullerene radical anion (C60(⋅-)), could be spectrally characterized. Owing to the close proximity of the donor and acceptor entities in the dyad and triad, the rate of charge separation, kCS , was found to be about 10(11)  s(-1), suggesting the occurrence of an ultrafast charge-separation process. Interestingly, although an order of magnitude slower than kCS , the rate of charge recombination, kCR , was also found to be rapid (kCR ≈10(10)  s(-1)), and both processes followed the solvent polarity trend DMF>benzonitrile>THF>toluene. The charge-separated species relaxed directly to the ground state in polar solvents while in toluene, formation of (3) corrole* was observed, thus implying that the energy of the charge-separated state in a nonpolar solvent is higher than the energy of (3) corrole* being about 1.52 eV. That is, ultrafast formation of a high-energy charge-separated state in toluene has been achieved in these closely spaced corrole-fullerene donor-acceptor conjugates., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)