Design strategies of metal free-organic sensitizers for dye sensitized solar cells: Role of donor and acceptor monomers

A series of metal free organic sensitizers have been designed and their optoelectronic properties for DSSC applications have been systematically investigated using density functional theory (DFT) and time dependent density functional theory (TD-DFT) methods. The role of donor/acceptor monomers on the electron donating/withdrawing abilities has been discussed and promising donor-acceptor combinations are screened. Based on this screening, some of novel metal free sensitizers have been designed and their electronic and spectral properties have been investigated using DFT/TDDFT methods. Our results show that the designed molecules are promising candidates to provide good performances as sensitizers in the DSSC applications. (C) 2014 Elsevier B.V. All rights reserved.