Influence of D-π-A system through linked unit of double and triple bonds in triarylene bridge for dye-sensitised solar cells

Novel organic dyes (YH-1-YH-4) containing olefin or acetylene as the π-spacer linkage in the triarylene bridge were synthesised. The photophysical and electrochemical properties of the dyes were characterised, and the dyes were then to fabricate dye-sensitised solar cells (DSSCs). We demonstrated the use of the D-π-A dipolar system by employing arylamine derivatives as an electron donor, triarylene with iterative olefin or acetylene as a π-bridge, and cyanoacrylic acid as an electron acceptor. YH-1 had olefin as a repeat unit in the triarylene bridge and had broad absorption, favourable short-circuit photocurrent density (J
_SC
), and favourable open-circuit voltage (V
_OC
) when used in film morphology with DCA as a coabsorbent. The optimal device exhibited a J
_SC
of 16.23 mA.cm
^-2
, a V
_OC
of 650 mV, and a fill factor of 0.67, corresponding to an overall conversion efficiency of 7.08%.