Anchorage of N3 dye-linked polyacrylic acid to TiO2/electrolyte interface for improvement in the performance of a dye-sensitized solar cell

A synthetic route was developed to link N3 dye to polyacrylic acid (PAA) using ethylenediamine (en) as the linker. The resulting complex, PAA–en–N3, was then coated onto a TiO₂ film. The modified TiO₂ film electrode (hereafter PAA–en–N3/TiO₂), when used as the photoanode in a dye-sensitized solar cell (DSSC), exhibited enhanced solar energy conversion efficiency compared with that of the usual DSSC with the N3/TiO₂ film electrode. The increase in efficiency was attributed to the increased open-circuit voltage (V_oc) and short-circuit photocurrent (J_sc). The increase in V_oc was attributed to the formation of a hydrophobic PAA–en–N3 layer on the TiO₂/electrolyte interface, while the increase in J_sc was attributed to the additional dye acquired by the TiO₂ film from the PAA–en–N3 complex.