Theoretical study on the structure–property relationship of D–A–π–A-type dye-sensitized solar cells: π-bridge and the side alkyl chain

Abstract

Two series of dyes have been designed and theoretically characterized 18 through density functional theory (DFT) and time-dependent density functional theory 19 (TD-DFT) to systematically explore the structure-property relationship of dyes with 20 D-A-π-A architecture and the performance of dye-sensitized solar cells (DSSC), 21 particularly the influence of π-bridge, including its alkyl side chain, adding additional 22 conjugate spacer, displacement and separation of π-bridge. Key parameters associated 23 with the short-circuit current density J sc and open-circuit photovoltage V oc were 24 characterized and detailedly analyzed. The whole analysis results manifest that dye 25 H1 should be the best candidate to fabricate DSSC owing to the best optical 26 absorption property (a broad absorption band from 300 nm to 900 nm for adsorbed 27 dye) and other outstanding parameters. 28 29 30 KEY WORDS: Dye-sensitized solar cells (DSSC); Structure-property relationship; 31 D-A-π-A architecture; Density functional theory (DFT); Time-dependent density 32 functional theory (TD-DFT)