| Autor: |
Chou-Pou Hsieh, Hsueh-Pei Lu, Chien-Lan Chiu, Cheng-Wei Lee, Shu-Han Chuang, Chi-Lun Mai, Wei-Nan Yen, Shun-Ju Hsu, Eric Wei-Guang Diau, Chen-Yu Yeh |
| Zdroj: |
Journal of Materials Chemistry; Feb2010, Vol. 20 Issue 6, p1127-1134, 8p |
| Abstrakt: |
A series of porphyrin dyes with an electron-donating group (EDG) attached at a meso-position (YD1–YD8) have been designed and synthesized for use as sensitizers in dye-sensitized solar cells (DSSC). The nature of the EDG exerts a significant influence on the spectral, electrochemical and photovoltaic properties of these sensitizers. Absorption spectra of porphyrins having an amino group show broadened Soret band and red-shifted Q bands with respect to those of reference porphyrin YD0. This phenomenon is more pronounced for porphyrins YD7and YD8that have a π-conjugated triphenylamine at the meso-position opposite the anchoring group. Upon introduction of an EDG at the meso-position, the potential for the first oxidation alters significantly to the negative whereas that for the first reduction changes inappreciably, indicating a decreased HOMO-LUMO gap. Results of density-functional theory (DFT) calculations support the spectroelectrochemical data for a delocalization of charge between the porphyrin ring and the amino group in the first oxidative state of diarylamino-substituted porphyrins YD1–YD4, which exhibit superior photovoltaic performance among all porphyrins under investigation. With long-chain alkyl groups on the diarylamino substituent, YD2shows the best cell performance with JSC= 13.4 mA cm−2, VOC= 0.71 V, and FF= 0.69, giving an overall efficiency 6.6% of power conversion under simulated one-sun AM1.5 illumination. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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