Rational designing and extra ordinary role of π-spacer towards enhancement of power conversion efficiency of dye sensitized solar cell: a theoretical prospective

Global energy demand is continuously surging due to population growth and growth of industrialization in this prospective, solar energy is one of the emerging solution. In the current investigation, D-π-A organic dyes ( 1–9 ) were designed by tuning the π-spacer and evaluated as sensitizers for dye-sensitized solar cells (DSSCs). Molecular orbital analysis confirmed that the optimal energy alignment for efficient electron transfer while absorption on TiO 2 study reveal that the performance for dyes with larger π-spacers particularly those containing sulphur and selenium were enhance the photo physical properties. Further, density of state (DOS), partial density of state (PDOS), natural bond orbital (NBO) and molecular electrostatic potential (MEP) analyses were providing deeper insight into electronic behaviour of the designed molecules. The calculated results infer that the designed dye–semiconductor were exhibited stable adsorption modes and favourable interactions. Impressively, the predicted power conversion efficiencies (PCE) reached up to 28.28% that demonstrate the potential of these engineered dyes molecules for high-performance DSSCs.