Effects of tethering alkyl chains for amphiphilic ruthenium complex dyes on their adsorption to titanium oxide and photovoltaic properties

On the correlation between dye coverage and photoelectrochemical performance in dye-sensitized solar cells

“…16 However, the shape of the Z907 concentration depth profiles is slightly different to that of N719. The Z907 profiles can rather be interpreted as double layers, a structure similar to that suggested by Ni et al, 18 while the profiles of N719 show a more gradual change from the maximum concentration to the uncovered substrate. The shape of the concentration depth profiles does not change with the Z907 coverage, which allows for the conclusion that the Z907 grows in islands, similarly to the N719.…”

“…A recent AFM study indicates that the dye molecule islands are typically of a size around 50 nm and even thicker than indicated by the previous NICISS studies. 18 In addition, a recent study by O'Regan and co-workers indicates that the photoelectron injection process may be more complex than previously thought. 19 In this work, we will study two of the most commonly used organometallic dyes, the N719 20 and Z907 21 dyes.…”

Imaging Dye Aggregation in MK-2, N3, N749, and SQ-2 dye···TiO2 Interfaces That Represent Dye-Sensitized Solar Cell Working Electrodes

“…The nanoaggregates were identified on amorphous substrates in this study. Dye nanoaggregates of N719 (the doubly deprotonated form of N3) on mesoporous substrates have also been found in an independent study by Merquet et al after a long-time sensitization ∼20 h. Meanwhile, Lin and co-workers have reported that molecules of alkyl-substituted N3 dyes could form nanoaggregates at a very early stage of sensitization and then re-dissolve and precipitate to form a monolayer when using dense TiO 2 substrates. , …”

“…Dye nanoaggregates of N719 (the doubly deprotonated form of N3) on mesoporous substrates have also been found in an independent study by Merquet et al 58 after a long-time sensitization ∼20 h. Meanwhile, Lin and co-workers have reported that molecules of alkyl-substituted N3 dyes could form nanoaggregates at a very early stage of sensitization and then re-dissolve and precipitate to form a monolayer when using dense TiO 2 substrates. 59,60 Parkinson et al showed that MK-2 dye molecules tend to form J-nanoaggregates on ZnO surfaces. 54 The mechanism of J-aggregation involves individual molecules connecting in a head-to-tail fashion, and having formed, these aggregates exhibit intrinsic anisotropic polarity that may promote further assembly along this head-to-tail projection.…”

Photoisomerization of the cyanoacrylic acid acceptor group – a potential problem for organic dyes in solar cells

“…However, this presumption has recently been challenged on the basis of direct experimental investigations on the adsorbed dye layers at different coverage levels, and the mode of anchoring is not obvious. [6][7][8] Nevertheless, the anchoring group has an essential function in the dye molecules, and is thus central to the dye function as a sensitizer in the DSC devices. We have therefore chosen the simplest triarylamine dye molecule of D-p-A type, the so-called L0 dye (Fig.…”