Efficient triphenylamine photosensitizers with alkoxy- or fluorine-substituted phenylene spacer for dye-sensitized solar cells

Two new organic sensitizers (TP1-2) containing triarylamine donor and a cyanoacrylic acid acceptor bridged by alkoxy- or fluorine-substituted phenylene spacer have been synthesized and explored as a sensitizer in dye-sensitized solar cells (DSCs). The absorption spectra, electrochemical and photovoltaic properties of TP1-2 are extensively investigated. The DSC based on dye TP1 shows the best photovoltaic performance: a short-circuit photocurrent density (J(SC)) of 13.5 mA cm(-2), an open-circuit photovoltage (V-OC) of 702 mV, and a fill factor (ff) of 0.68, corresponding to an overall conversion efficiency of 6.4% under standard global AM1.5 solar light conditions. The results demonstrate that structural modification of substituting groups on pi-spacer is importance for realizing a high efficiency DSC.