Merocyanine dye-sensitization of polythiophene in a conjugated polymer/TiO2 p-n hetero-junction solar cell

In the blended solid of merocyanine (MC) and polythiophene (PTh)/TiO2 p-n hetero-junction solar cells, a hole transfer from the excited state of MC to the ground-state of PTh accelerated the charge separation in the depletion layer formed at the TiO2/MC+PTh interface, enhancing the photovoltaic properties. That is, the blended solar cell is not a so-called Gratzel cell being sensitized by mono-layer dyes chemically adsorbed on the TiO2 electrode, but rather the enhanced photovoltaic properties are attributable to the dye- sensitization of the conjugated polymer.