RT Journal Article
T1 Ru(II)-phthalocyanine sensitized solar cells: the influence of co-adsorbents upon interfacial electron transfer kinetics
A1 Morandeira Ramírez, Ana
A1 López Duarte, Ismael
A1 O'Regan, Brian
A1 Martínez Díaz, María Victoria
A1 Forneli Rubio, María Amparo
A1 Palomares Gil, Emilio
A1 Torres Cebada, Tomás
A1 Durrant, James Robert
AB The development of efficient red sensitizer dyes is essential for the optimization of dye-sensitized photoelectrochemical solar cells. Ru-phthalocyanines are good candidates because they show high absorbance in the red while their axial ligands hinder the formation of aggregates, a recurrent problem among phthalocyanine dyes. In this paper, we present the photophysics and photovoltaic device performance for a series of novel Ru-phthalocyanines. We focus in particular upon the origin of the enhancement in device performance observed in the presence of two additives, Li+ and chenodeoxycholic acid. The addition of Li+ lowers the conduction band edge of the TiO2 semiconductor leading to a higher electron injection yield and a higher photocurrent in the device. The increases in injection yield and photocurrent are large for these sensitizers, compared to the widely studied ruthenium bipyridyl dye N719, due to the relatively slow injection dynamics, emphasizing the importance of injection yield in limiting device performance for this Ru-phthalocyanine dye series. Of particular interest is the effect of chenodeoxycholic acid. This coadsorbent dramatically enhances the photocurrent of the studied devices without lowering the photovoltage. Unlike previous studies, in this case the photocurrent rise can not be attributed to an increment in the electron injection yield due to the effect of the coadsorbent hindering the formation of dye aggregates. Photophysical measurements instead show that the slower recombination of dye cations with the TiO2 electrons and faster regeneration of the dye cations by the electrolyte are the reasons for the enhanced photocurrent.
PB The Royal Society of Chemistry
SN 0959-9428
YR 2009
FD 2009
LK https://hdl.handle.net/20.500.14352/100090
UL https://hdl.handle.net/20.500.14352/100090
LA eng
NO Morandeira A, López-Duarte I, O’Regan B, Martínez-Díaz MV, Forneli A, Palomares E, et al. Ru(II)-phthalocyanine sensitized solar cells: the influence of co-adsorbents upon interfacial electron transfer kinetics. J Mater Chem 2009;19:5016. https://doi.org/10.1039/b904179f.
DS Docta Complutense
RD 17 jul 2024