Highly Efficient p-Type Dye-Sensitized Solar Cells based on Tris(1,2-diaminoethane)Cobalt(II)/(ffl) Electrolytes

摘要

The projected low manufacturing costs of dye-sensitized solar cells (DSCs) has made them attractive alternatives to traditional solar cells. In the conventional photoanodic DSCs (n-DSCs), photocurrent generation results from dye-sensitized electron injection into n-type semiconductors, such as TiO2. In contrast, for dye-sensitized photocathodes (p-DSC), electron transfer takes place from the valence band of the p-type semiconductor (NiO being the most commonly used to date) to the photoexcited dye. The prospect of using p-DSCs as components in dye-sensitized tandem devices (pn-DSCs) has recently generated renewed interest in p-DSCs. Photocathodes employing the most efficient p-DSC sensitizer (PMI-6T-TPA; see Figure 1) reported to date in conjunction with a mesoporous NiO nanoparticles film and an I~-/I3~- based electrolyte achieved efficiencies of up to 0.41% under simulated sunlight (1000 Wm~(-2), AM 1.5 G). The PMI-6T-TPA-sensitized photocathode exhibits open-circuit voltages (V_(oc)) of up to 218 mV and short-circuit current densities (J_(SC)) of up to 5.35 mA cm~(-2). Absorbed photon to charge carrier conversion efficiencies (APCE) up to 96% have been observed for these p-DSCs.