Donor functionalized quinoline based organic sensitizers for dye sensitized solar cell (DSSC) applications: DFT and TD-DFT investigations.

The influence of different donor groups in quinoline based novel sensitizers for dye sensitized solar cell (DSSC) applications is analyzed by using density functional theory (DFT) and time dependent density functional theory (TD-DFT). Quinoline and donor functionalized quinoline based novel organic sensitizers have been designed with different π-spacers for DSSC applications. The ground state molecular structure of novel organic sensitizers is fully optimized by DFT calculation in both gas and chloroform phases. Electronic absorption characteristics are predicted by the TD-DFT calculation in both gas and chloroform phases. The polarizable continuum model is used for solvent phase optimization. The net electron transfer from the donor to acceptor is calculated from natural bond orbital (NBO) analysis. The injection energy and dye regeneration energy values are also calculated. Different donor groups are substituted in quinoline, and these substituted quinoline donors are used as the donor group. Cyanovinyl and thiophene groups act as π-spacers and cyanoacrylic acid acts as an acceptor. DFT and TD-DFT studies of the quinoline and donor functionalized quinoline sensitizers show that the coumarin based and N-hexyltetrahydroquinoline donors are more efficient for DSSC application.