Additional donor bridge as a design approach for multi-anchoring dyes for highly efficient dye-sensitized solar cells

Abstract

© 2017 Elsevier B.V. This work presents an approach for designing efficient multi-anchoring dyes for dye-sensitized solar cells by using additional donor as a bridging group between donor–acceptor (D–A) side arms. With triarylamine as the additional donor and phenothiazine-cyanoacrylic acid as the D–A side arm, the multi-anchoring dyes exhibited higher molar extinction coefficients in the intramolecular charge transfer bands, less dye aggregation on the TiO2 surface, and better DSSC performance than that of the mono-anchoring reference dye. The best cell efficiency of 7.06% was obtained from the di-anchoring dye with two additional donor units T2P2 showing the largest charge recombination resistance of 99.7 Ω, open circuit voltage of 0.83 V, and short-circuit photocurrent density of 12.72 mA cm−2. The improvement in performance of the designed dyes suggests that additional donor is a potential bridging group for efficient multi-anchoring sensitizers.