Enhancement in the performance of dye-sensitized solar cells containing ZnO-covered TiO2 electrodes prepared by thermal chemical vapor deposition

A ZnO-covered TiO2 (denoted as ZnO/TiO2) film was prepared by incorporating a small quantity of particulate ZnO in a TiO2 matrix by thermal chemical vapor deposition. When used in a dye-sensitized solar cell, an enhancement was observed in both short-circuit photocurrent (Jsc) and open-circuit voltage (Voc) by 12% and 17%, respectively, relative to those of a cell containing a bare TiO2 film. The observed Jsc enhancement is attributed to the increase in the surface area of the ZnO/TiO2 film, and the Voc enhancement to the formation of a potential barrier by ZnO at TiO2/electrolyte interface. The films were characterized by FE-SEM, EDX, and XRD.