title: Screening π-conjugated bridges of organic dyes for dye-sensitized solar cells with panchromatic visible light harvesting.
abstract: Developing highly efficient organic dyes with panchromatic visible light harvesting for dye-sensitized solar cells (DSSCs) is still one of the most important scientific challenges. Here, we design a series of phenothiazine derivative organic dyes with donor-π-acceptor (D-π-A) structure using density functional theory (DFT) and time-dependent DFT (TDDFT) based on experimentally synthesized typical SH-6 organic dyes. Results indicate that the newly designed BUCT13 - BUCT30 dyes show smaller HOMO-LUMO energy gaps, higher molar extinction coefficients and obvious redshifts compared to the SH-6 dye, and the maximum absorption peaks of eight dyes are greater than 650 nm among the newly designed dyes. In particular, BUCT27 exhibits a 234 nm redshift and the maximum molar extinction coefficient with an increment of about 80% compared to the SH-6 dye. BUCT19 exhibits not only a 269 nm redshift and higher molar extinction coefficient with an increment of about 50% compared to the SH-6 dye, but the extremely broad absorption spectrum covering the entire visible range up to the near-IR region of 1200 nm. It is expected that this work can provide a new strategy and guidance for the investigation of these dye-sensitized devices.
authors.affiliation: State Key Laboratory of Organic-Inorganic Composites, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China. Science College, China University of Petroleum, Beijing 102249, People's Republic of China.
authors.forename: Zhenqing
authors.initials: Z
authors.lastname: Yang
authors.forename: Chunmeng
authors.initials: C
authors.lastname: Liu
authors.forename: Changjin
authors.initials: C
authors.lastname: Shao
authors.forename: Xiaofei
authors.initials: X
authors.lastname: Zeng
authors.forename: Dapeng
authors.initials: D
authors.lastname: Cao