New designed push-pull organic dyes based on the conjugated π-spacers for application in dye-sensitized solar cells: a computational chemistry study

In this research, four novel push-pull organic dyes with D–π–A structural configuration with a variety of π-spacer segments were investigated from the structural, electronic, optical and photovoltaic characteristics viewpoints, using density functional theory approaches. In fact, we modulated the π-spacer segment by inserting C–C double and triple bonds and phenyl and anthracene units to examine the further improvements in the light-harvesting capability of these dyes in dye-sensitized solar cells (DSSCs). It was corroborated that using C–C triple bond in conjunction with phenyl group as π-linker will reduce the light-harvesting efficiency values in comparison with C–C double bond group, leading to the lower power conversion efficiency of DSSCs. In this context, we made a revision and presented a newly designed dye structure by inserting anthracene together with C–C triple bond and investigated their notable planar π-conjugation effect as an excellent candidate for DSSCs applications.