Photoelectrochemical response of poly(3-hexylthiophene) and poly(2,3-diethylquinoxaline-5,8-diyl) in aqueous media

The photoelectrochemical properties of poly(3-hexylthiophene) (P3HT) and poly(2,3-diethylquinoxaline-5,8-diyl) (PDEQx) thin films on ITO (indium-tin oxide) electrodes were investigated in aqueous media. Photoirradiation of the P3HT-coated electrode resulted in cathodic photocurrents in the presence of methyl benzoylformate, whereas the PDEQx-coated electrode generated stable anodic photocurrents in the presence of 2-mercaptoethanol. The action spectra indicate that photoexcitations of the polymers cause photoelectrochemical reactions. The films of P3HT and PDEQx exhibit a typical photochemical response of p- and n-type semiconducting materials, respectively.