Photovoltaic Properties and Long-Term Durability of Porphyrin-Sensitized Solar Cells with Silicon-Based Anchoring Groups.

ABSTRACT: Anchoring groups for dye-sensitized solar cells (DSSCs) play a decisive role in high-power conversion efficiency (?) and long-term cell durability. To date, a carboxylic acid is the most widely used anchoring group for DSSCs. However, the carboxylic acid tends to dissociate from a TiO₂ surface during the cell operation as well as in the presence of water. Considering that the dye dissociation from TiO₂ leads to a decrease in the cell performance, stable anchoring groups are highly desirable to achieve long-term durability of DSSCs toward their practical application. In this study, we designed and synthesized a series of porphyrin dyes with the triethoxysilyl anchoring groups, ZnPSi1, ZnPSi2, and ZnPSi3, to evaluate the effects of the silicon-based anchoring group on cell durability and photovoltaic properties. The DSSCs based on ZnPSi1, ZnPSi2, and ZnPSi3 exhibited moderate ?-values of 2.2, 4.7, and 2.3%, respectively. It is noteworthy that the ?-value of the DSSC based on ZnPSi2 (4.7%) is the highest among DSSCs based on porphyrin dyes with silicon-based anchoring groups. The moderate ?-values are mainly attributed to the low charge collection efficiency originating from the low surface coverage and plausible tilted geometry of the dyes on TiO₂. More importantly, we demonstrated that the DSSC based on ZnPSi2 revealed higher long-term cell durability under illumination than that based on reference porphyrin YD2 -o -C8 having a conventional carboxylic acid anchoring group.

SUBMITTER: Higashino T 

PROVIDER: S-EPMC6645028 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature