The degradation mechanisms of Reverse Bias (RB) stressed Dye Solar Cells (DSCs), sensitized with cisbis( isothiocyanato)bis(2,20-bipyridyl-4,40-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium (N719, Red Dye) and with cis-dicyano-bis(2,20-bipyridyl-4,40-dicarboxylic acid) ruthenium(II) (Ru505, Orange Dye) have been studied by means of resonance micro-Raman and UV-Vis spectroscopy. For N719 sensitized devices, the visible degradation induced by the stress tests involves both electrolytic solution and the sensitizer: the electrolyte suffers gas bubble formation and loss of solvent, while the dye cannot be regenerated and undergoes irreversible chemical changes. Confocal Raman imaging and UV-Vis absorption spectra confirmed that in regions where the electrolyte was absent, the detachment of the thiocyanate ligand (SCN) from the dye is favored. On the other hand, measurements carried out on DSCs realized with the bis-cyano dye (Ru505) do not show dye modifications during the RB stress. We also clarify that the apparent N719 dye bleaching in particular zones of the cell active area, is not related to dye desorption from the TiO2 layer, but to loss of solvent and to dye chemical changes, which are responsible for a characteristic blue shift in the absorption spectrum.

Agresti, A., Pescetelli, S., Quatela, A., Mastroianni, S., Brown, T.m., Reale, A., et al. (2014). Micro-Raman analysis of reverse bias stressed dye-sensitized solar cells. RSC ADVANCES, 4, 12366-12375 [10.1039/C3RA47797E].

Micro-Raman analysis of reverse bias stressed dye-sensitized solar cells

Agresti, A;PESCETELLI, SARA;BROWN, THOMAS MEREDITH;REALE, ANDREA;DI CARLO, ALDO
2014

Abstract

The degradation mechanisms of Reverse Bias (RB) stressed Dye Solar Cells (DSCs), sensitized with cisbis( isothiocyanato)bis(2,20-bipyridyl-4,40-dicarboxylato)-ruthenium(II)bis-tetrabutylammonium (N719, Red Dye) and with cis-dicyano-bis(2,20-bipyridyl-4,40-dicarboxylic acid) ruthenium(II) (Ru505, Orange Dye) have been studied by means of resonance micro-Raman and UV-Vis spectroscopy. For N719 sensitized devices, the visible degradation induced by the stress tests involves both electrolytic solution and the sensitizer: the electrolyte suffers gas bubble formation and loss of solvent, while the dye cannot be regenerated and undergoes irreversible chemical changes. Confocal Raman imaging and UV-Vis absorption spectra confirmed that in regions where the electrolyte was absent, the detachment of the thiocyanate ligand (SCN) from the dye is favored. On the other hand, measurements carried out on DSCs realized with the bis-cyano dye (Ru505) do not show dye modifications during the RB stress. We also clarify that the apparent N719 dye bleaching in particular zones of the cell active area, is not related to dye desorption from the TiO2 layer, but to loss of solvent and to dye chemical changes, which are responsible for a characteristic blue shift in the absorption spectrum.
Pubblicato
Rilevanza internazionale
Articolo
Esperti anonimi
Settore ING-INF/01 - Elettronica
English
Agresti, A., Pescetelli, S., Quatela, A., Mastroianni, S., Brown, T.m., Reale, A., et al. (2014). Micro-Raman analysis of reverse bias stressed dye-sensitized solar cells. RSC ADVANCES, 4, 12366-12375 [10.1039/C3RA47797E].
Agresti, A; Pescetelli, S; Quatela, A; Mastroianni, S; Brown, Tm; Reale, A; Bignozzi, C; Caramori, S; DI CARLO, A
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
pXX_mRaman reverse RSC Adv., 2014, 4, 12366.pdf

non disponibili

Licenza: Copyright dell'editore
Dimensione 944.87 kB
Formato Adobe PDF
944.87 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/120858
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 19
  • ???jsp.display-item.citation.isi??? ND
social impact