Dye Sensitization of a Zinc Oxide Electrode Studied by a Potential Modulation Technique

Article abstract of DOI:10.1021/j150643a038

A potential modulation technique has been developed and applied to the study of the dye sensitization phenomena.The lifetimes of oxidized sensitizing dyes, Rose Bengal and Rhodamine B, which are formed by electron transfer from the excited states to the conduction band of a ZnO electrode, are determined to be 60 +/- 15 and 100 +/- 25 ms, respectively.The rate constants for electron transfer from potassium iodide, L-tryptophan, and hydroquinone to oxidized Rose Bengal are also determined to be 1.2 (+/-0.5) * 10⁴, 4.0 (+/-1.7) * 10⁵, and 3.3 (+/-1.4) * 10⁶ M^-1 s^-1, respectively.