The improved performance of dye-sensitized solar cells using co-sensitization and polymer gel electrolyte

To investigate the photovoltaic capabilities as a sensitizer and co-sensitizer for dye-sensitized solar cells (DSSCs), a new metal-free organic dye (CDIB) was synthesized. In addition, different concentrations of 1-n-hexyl-3-methylimidazolium iodide ionic liquid (IL) doped poly(vinylidene fluoride-hexafluoropropylene) gel polymer electrolytes are prepared and the high conductive electrolyte is used to fabricate the devices. The device having CDIB sensitizer and IL-15% electrolyte showed an efficiency of 1.86%. Further, the effect of CDIB co-sensitization on Z907 is examined. Consequently, the power conversion efficiency of DSSC with co-sensitized dye is raised by 23.29%, from 4.55 to 5.61%, when compared to DSSCs with individual dyes. This improvement is mostly due to an increase in a short-circuit current density and open-circuit voltage. Highlights: Co-sensitization is being used to enhance the performance of DSSCs. Poly(vinylidene fluoride-hexafluoropropylene)-based gel polymer electrolytes doped with different amounts of 1-n-hexyl-3-methylimidazolium iodide were prepared for improving the conductivity of electrolyte. A co-sensitized DSSC has an efficiency of 5.61%. With co-sensitization, both V_OC and J_SC increased significantly.