title: Molecular engineering and theoretical investigation of organic sensitizers based on indoline dyes for quasi-solid state dye-sensitized solar cells.
abstract: Novel indoline dyes, I-1-I-4, with structural modification of π-linker group in the D-π-A system have been synthesized and fully characterized. Molecular engineering through expanding the π-linker segment has been performed. The ground and excited state properties of the dyes have been studied by means of density functional theory (DFT) and time-dependent DFT (TD-DFT). Larger π-conjugation linkers would lead to broader spectral response and higher molar extinction coefficient but would decrease dye-loaded amount on TiO(2) electrode and LUMO level. While applied in DSSCs, the variation trends in short-circuit current density (J(sc)) and open-circuit voltage (V(oc)) were observed to be opposite to each other. The internal reasons were studied by experimental data and theoretical calculations in detail. Notably, I-2 showed comparable photocurrent values with liquid and quasi-solid state electrolyte, which suggested through molecular engineering of organic sensitizers the dilemma between optical absorption and charge diffusion lengths can be balanced well. Through studies of photophysical, electrochemical, and theoretical calculation results, the internal relations between chemical structure and efficiency have been revealed, which serve to enhance our knowledge regarding design and optimization of new sensitizers for quasi-solid state DSSCs, providing a powerful strategy for prediction of photovoltaic performances.
authors: College of Chemistry and Material Science, Hebei Normal University, 113 East Yuhua Road, Shijiazhuang, Hebei, 050016, PR China. liubo@mail.hebtu.edu.cn
authors: Bo
authors: B
authors: Liu
authors: Wenjun
authors: W
authors: Wu
authors: Xiaoyan
authors: X
authors: Li
authors: Lei
authors: L
authors: Li
authors: Shaofu
authors: S
authors: Guo
authors: Xiaoru
authors: X
authors: Wei
authors: Weihong
authors: W
authors: Zhu
authors: Qingbin
authors: Q
authors: Liu
mesh_terms: D004396:Coloring Agents / Q000138:chemical synthesis / Q000737:chemistry*; D011211:Electric Power Supplies; D007211:Indoles / Q000138:chemical synthesis / Q000737:chemistry*; D011789:Quantum Theory
chemical_list: D004396:Coloring Agents; D007211:Indoles; C057812:indoline