Theoretical Studies of Electronic Structure and Photophysical Properties of a Series of Indoline Dyes with Triphenylamine Ligand

Abstract EN

To design efficient organic sensitizer, a series of D-π-A indoline dyes with different donor parts have been investigated by density functional theory (DFT) and time-dependent DFT (TD-DFT) approach.

The molecular geometries, frontier molecular orbitals, and absorption spectra of these dyes have been systematically investigated to provide comprehensive understanding of the structure-property relationships.

Compared with D149, our designed dyes have proper HOMO and LUMO energy level, narrowed HOMO-LUMO energy gap, and broadened absorption band by introducing the N(CH3)2 and N(phenyl)2 groups at the donor part.

Furthermore, the dimeric dyes and dye-(TiO2)6 systems have been optimized by DFT method to simulate the intermolecular interactions, as well as interaction between the dyes dimmers and semiconductor interface, respectively.

Through the analyses of absorption energies (Eads), energy levels of the HOMO and LUMO, light harvesting efficiency (LHE), and the driving force of electrons injections (ΔGinject), it is found that the designed dyes should have improved optical properties by importing the N(CH3)2 group.

This work is hoped to provide a theoretical guiding role in design of new dyes for dye-sensitized solar cells.