title: Controlling light absorption and photoelectric properties of coumarin-triphenylaminedye by different acceptor functional groups.
abstract: The ground state and excited state properties of three coumarin dyes, ZCJ1, ZCJ2 and ZCJ3, including ground state structures, energy levels, absorption spectra and driving forces of electron injection, were investigated via density functional theory (DFT) and time-dependent density functional theory (TD-DFT). In addition, five new molecules ZCJ3-1, ZCJ3-2, ZCJ3-3, ZCJ3-4 and ZCJ3-5 were designed through the introduction of a -CN group into molecule ZCJ3. The ground state and excited state properties of the five designed molecules were also calculated and compared with that of the original molecule, aiming to investigate the effect of different position of -CN groups on the optical and electrical properties of dye molecules. Moreover, the external electric field was taken into account. The results indicated that all three original molecules have better absorption within the visible-light range, and the molecule with a thiophene-thiophene conjugated bridge enables a red shift of the absorption spectrum. The molecule with a thiophene-benzene ring conjugated bridge enables the increase of driving force of electron injection. The energy levels, spectra and driving force of electron injection for the designed molecules are discussed in terms of studying their potential utility in dye-sensitized solar cells.
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China.
authors: Chaofan
authors: C
authors: Sun
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China.|School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian, 116024, People's Republic of China.
authors: Yanpeng
authors: Y
authors: Bai
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China. yzli@nefu.edu.cn.
authors: Yuanzuo
authors: Y
authors: Li
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China.
authors: Dejiang
authors: D
authors: Liu
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China.
authors: Beibei
authors: B
authors: Xu
authors: College of Science, Northeast Forestry University, Harbin, 150040, Heilongjiang, China.
authors: Qungui
authors: Q
authors: Wang
keywords: Absorption spectrum; DSSC; Density functional theory; Electron injection