Computational studies of the influence of auxiliary acceptors in the D-A'-π-A structure of organic dyes on the photovoltaic performance of dye solar cells

Context A series of five organic dyes (M i , i = 1–5) of the D-A’-π-A structure were designed based on reference dye (Ref), and the influence of different auxiliary acceptors (A’) on their efficiency in dye-sensitized solar cells (DSSC). Methods Was studied theoretically using density functional theory (DFT) and time-dependent DFT (TD-DFT) methods. In this context, the electronic structures, optical properties, and the parameters influencing the power conversion efficiency (PCE), such as light harvesting efficiency (LHE), electron injection driving force (∆G inject. ), and open circuit photo-voltage (V OC ), have been evaluated and discussed. The modification of the auxiliary acceptor (A’) in the D-A’-π-A structure of the designed organic dyes has the advantage of significantly decreasing the band gap, which leads to the broadening of the absorption band that is red-shifted and improves the photovoltaic characteristics compared to Ref . Theoretical results reveal that M 1 , and M 5 can be used as excellent sensitizer candidates for DSSC applications.