## 3 Results
Generally, the higher efficiency of the DSSC of sample 1 (cf. Figure 2) is also evident in the I-U curves depicted in Figure 3.  
Figure 3: I-U curves of PAN blended with PEO (samples 1 and 2) and PAN (sample 3) GPEs for: (**a**) day 0; (**b**) day 28; (**c**) day 59; and (**d**) day 110. Figure 2: Efficiencies of PAN blended with PEO (samples 1 and 2) and PAN (sample 3) GPEs for 120 days. In Figure 4, the efficiencies of the DSSCs with GPEs consisting of ABS, PAN and PVDF, partly blended with PEO, are presented. For all blended GPEs, samples 4, 6 and 8, an increase in efficiency in the first week was identifiable, while the efficiency of the corresponding PEO-less samples (5, 7 and 9) stayed constant or even decreased. DSSCs with a two-component GPE had higher efficiencies than their equivalents without PEO during the entire measurement period. However, except for sample 6, which increased slightly after 100 days, the two-component GPE also dropped over time. In comparison, sample 8, PVDF with PEO, showed the consistently best energy conversion. Sample 4, containing a blend with ABS, had slightly lower efficiencies with a significant decrease in week 8, while PVA blended with PEO (sample 6) fell off after the first week and stayed at low efficiencies. For further comparison, Figure 5 shows the measured I-U curves for days 0, 28, 59 and 110 for the DSSCs of samples 4 to 9. At day 0, the I\({}_{\text{SC}}\) and U\({}_{\text{OC}}\) values were roughly equal (sample 5 shows a higher I\({}_{\text{SC}}\) and sample 7 a lower U\({}_{\text{OC}}\)). On day 28 a slight decrease for sample 8 was seen, whereby it always had the highest P\({}_{\text{MPP}}\). Days 28 and 59 showed a further decrease of U\({}_{\text{OC}}\) for sample 4 while I\({}_{\text{SC}}\) rises to a maximum value of 0.065 mA on day 28 and then dropped again. After day 28, the I\({}_{\text{SC}}\) and U\({}_{\text{OC}}\) values of samples 4 to 9 decreased with the aging process, with the values of sample 8 remaining comparatively the highest. In general, the progression of the curves corresponded to the efficiencies depicted in Figure 4 before. As described above, PEO blended GPEs resulted generally in higher efficiencies and improved long-term stability compared to GPEs without PEO. Therefore, in Figure 6 only the polymer/PEO blends are compared to a reference DSSC with a commercial liquid electrolyte. While all GPE DSSCs started at low and similar efficiency values, the reference DSSC had its highest efficiency at day 0 and was steadily decreasing thereafter. All GPE DSSCs reached a maximum efficiency between the first and third week. Sample 6 (PVA/PEO) and sample 8 (PVDF/PEO) reached values around 0.008% and 0.005% at day 5, sample 4 (ABS/PEO) reached a maximum efficiency of 0.007% at day 13 and the highest value of 0.0125% for sample 1 (PAN/PEO) was reached at day 19. Although all DSSCs decreased after their peak efficiency, their decline was far less than that of the reference. After approximately 50 days, the efficiencies of the GPE DSSCs decreased only slightly until the end of the observed period. It is also worth mentioning that the GPE DSSC efficiency values on day 120 have the same order from highest to lowest like the peak efficiency values reached over the course of the measurement. Figure 4: Efficiencies of ABS blended with PEO (sample 4), ABS (sample 5), PVA blended with PEO (sample 6), PVA (sample 7) and PVDF blended with PEO (sample 8) and PVDF (sample 9) GPEs for 120 days. Figure 5: I-U curves of ABS blended with PEO (sample 4), ABS (sample 5), PVA blended with PEO (sample 6), PVA (sample 7), and PVDF blended with PEO (sample 8) and PVDF (sample 9) GPEs for: (**a**) day 0; (**b**) day 28; (**c**) day 59; and (**d**) day 110. Table 1.0 Efficiencies of PAN blended with PEO (sample 1), ABS blended with PEO (sample 4), PVA blended with PEO (sample 6), PVDF blended with PEO (sample 8) GPEs and a reference DSSC for 120 days. Figure 7 shows typical I-U curves of the PEO blended GPEs and the reference DSSC.