1138342-10-5Relevant academic research and scientific papers
Light-Induced Regiospecific Bromination of meso-Tetra(3,5-di-tert-butylphenyl)Porphyrin on 2,12 β-Pyrrolic Positions
Di Carlo, Gabriele,Orbelli Biroli, Alessio,Tessore, Francesca,Rizzato, Silvia,Forni, Alessandra,Magnano, Giulia,Pizzotti, Maddalena
, p. 4973 - 4980 (2015)
The antipodal introduction of two bromine atoms on the 2,12 β-pyrrolic position of 5,10,15,20-tetra(3,5-di-tert-butylphenyl)porphyrin was successfully achieved by a light-induced reaction of the substrate with excess NBS. Complexation with NiII of the major regioisomer led to good quality crystals, suitable for X-ray structure determination with unprecedented probability levels. The regiospecific character of the synthetic procedure and the exactness of the bromine atom position assignment were thus confirmed, suggesting an unexpected electrophilic aromatic substitution pathway rather than a free-radical halogenation process. A QTAIM topological analysis on the DFT-optimized wave function of the monosubstituted free-base porphyrin intermediate carrying a bromine atom in C2 β-pyrrolic position confirmed the largest negative charge for the C12 carbon atom in antipodal position, in agreement with the proposed electrophilic aromatic substitution mechanism. (Figure Presented).
Tetraaryl ZnII porphyrinates substituted at β-pyrrolic positions as sensitizers in dye-sensitized solar cells: A comparison with meso-disubstituted push-pull ZnII porphyrinates
Di Carlo, Gabriele,Orbelli Biroli, Alessio,Pizzotti, Maddalena,Tessore, Francesca,Trifiletti, Vanira,Ruffo, Riccardo,Abbotto, Alessandro,Amat, Anna,De Angelis, Filippo,Mussini, Patrizia R.
supporting information, p. 10723 - 10740 (2013/08/23)
A facile and fast approach, based on microwave-enhanced Sonogashira coupling, has been employed to obtain in good yields both mono- and, for the first time, disubstituted push-pull ZnII porphyrinates bearing a variety of ethynylphenyl moieties at the β-pyrrolic position(s). Furthermore, a comparative experimental, electrochemical, and theoretical investigation has been carried out on these β-mono- or disubstituted ZnII porphyrinates and meso-disubstituted push-pull ZnII porphyrinates. We have obtained evidence that, although the HOMO-LUMO energy gap of the meso-substituted push-pull dyes is lower, so that charge transfer along the push-pull system therein is easier, the β-mono- or disubstituted push-pull porphyrinic dyes show comparable or better efficiencies when acting as sensitizers in DSSCs. This behavior is apparently not attributable to more intense B and Q bands, but rather to more facile charge injection. This is suggested by the DFT electron distribution in a model of a β- monosubstituted porphyrinic dye interacting with a TiO2 surface and by the positive effect of the β substitution on the incident photon-to-current conversion efficiency (IPCE) spectra, which show a significant intensity over a broad wavelength range (350-650 nm). In contrast, meso-substitution produces IPCE spectra with two less intense and well-separated peaks. The positive effect exerted by a cyanoacrylic acid group attached to the ethynylphenyl substituent has been analyzed by a photophysical and theoretical approach. This provided supporting evidence of a contribution from charge-transfer transitions to both the B and Q bands, thus producing, through conjugation, excited electrons close to the carboxylic anchoring group. Finally, the straightforward and effective synthetic procedures developed, as well as the efficiencies observed by photoelectrochemical measurements, make the described β-monosubstituted ZnII porphyrinates extremely promising sensitizers for use in DSSCs. Copyright
Synthesis and characterization of β-pyrrolic functionalized porphyrins as sensitizers for dye-sensitized solar cells
Sirithip, Kanokkorn,Morada, Somphob,Namuangruk, Supawadee,Keawin, Tinnagon,Jungsuttiwong, Siriporn,Sudyoadsuk, Taweesak,Promarak, Vinich
, p. 2435 - 2439 (2013/06/26)
New β-pyrrolic functionalized porphyrins with donor-π-acceptor character were synthesized and characterized as dye sensitizers for dye-sensitized solar cells. Two types of π-conjugated spacers, namely benzene and thiophene rings, with cyanoacrylic acid as an acceptor were linked to the porphyrin ring at the β-pyrrolic position. These porphyrins showed high thermal and electrochemical stability. As sensitizers, the porphyrin dye bearing a thiophene ring as the π-conjugated spacer gave better cell performance with a short-circuit photocurrent density (Jsc) of 4.57 mA cm -2, an open-circuit voltage (Voc) of 0.59 V, and a fill factor (ff) of 0.59, corresponding to an overall conversion efficiency (η) of 1.94%.
PORPHYRIN-BASED PHOTOSENSITIZER DYES FOR DYE-SENSITIZED SOLAR CELLS
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Page/Page column 12, (2010/06/13)
This invention relates to photosensitizer dyes for dye-sensitized solar cells. The photosensitizer dyes are porphyrin-based zinc complexes represented by the following general formulae (100) and (200). wherein A is represented by one of the following formulae (111)?(118), wherein Z1?Z10 independently represent a hydrogen atom (H), lithium (Li), sodium (Na), or tetra-alkyl ammonium group (as represented by the following general formula (120)), wherein X1?X4 independently represent CmH2m+1 (m=1?6), and B, C, D, and E independently represent one of the following formulae (131)?(140), wherein Ra?Rz are independently selected from the group consisting of H, CmH2m+1 (m=1?15), OCpH2p+1 (p=1?15), CH2[OC2H4]nOCH3 (n=1?30), and [OC2H4]qOCH3 (q=1?30).
Novel zinc porphyrin sensitizers for dye-sensitized solar cells: Synthesis and spectral, electrochemical, and photovoltaic properties
Lee, Cheng-Wei,Lu, Hsueh-Pei,Lan, Chi-Ming,Huang, Yi-Lin,Liang, You-Ren,Yen, Wei-Nan,Liu, Yen-Chun,Lin, You-Shiang,Diau, Eric Wei-Guang,Yeh, Chen-Yu
supporting information; experimental part, p. 1403 - 1412 (2009/08/07)
Novel meso- or β-derivatized porphyrins with a carboxyl group have been designed and synthesized for use as sensitizers in dye-sensitized solar cells (DSSCs). The position and nature of a bridge connecting the porphyrin ring and carboxylic acid group show
