Investigation on the Energy Conversion of Dye-Sensitized Solar Cells Based on TiO_2 Core/Shell Using Metal Oxide as a Barrier Layer

摘要

Photo-electrochemical solar cells based on a core-shell structure including ZnO shell and TiO_2 cove, have been fabricated with ruthenium bipyridyl complex (N719) as the sensitizer. Compared with the pure anatase TiO_2, the ZnO-covered TiO_7 film possesses outstanding ability to transport electrons with an overall power conversion efficiency of 3.72. Elctrochemical study shows that surface modification of TiO_2 film with ZnO can increase the concentration of free electrons in the conduction band of TiO_2. This remit implies that the charge recombination is reduced in process of electron transport through the TiOi porous film, which can decrease the photocurrent loss and hence improve Dye-Sensitized solar ceils (DSSCs) efficiency. This result indicates that optimization of TiO_2 porous network fabrication condition is efficient, for the improvement of TiO_2 based DSSCs performances.