PEO/PVdF–HFP electrolytes for natural dye sensitized solar cell applications: effect of modified nano-TiO2 on electrochemical and photovoltaic performance

Abstract

Poly ethylene oxide (PEO) and Polyvinylidene fluoride-co-hexaflouropropylene (PVdF-HFP) blend electrolytes filled with surface modified TiO 2 nanofillers were prepared by solvent casting method. The ionic conductivity is increased about 7.02 9 10 -4 S/cm with the incorporation of surface modified TiO 2 nanoparticles upto 7 wt %, where the ionic conductivity was about 7.94 9 10 -5 S/cm with the addition of unmodified counterpart as the filler within PEO/PVdF-HFP blends. Similarly, ionic mobility, charge carrier concentration, ion diffusion coefficient also found to increase with the addition of surface modified TiO 2 nanoparticles. XRD results showed the change in the crystalline phase of PEO/PVdF-HFP blend electrolyte with the addition of surface modified TiO 2 . The effect of the TiO 2 nanoparticles surface functionality on the degree of crystallinity of the polymer matrix was analyzed using DSC. The distribution of nanoparticles within the PEO/PVdF-HFP was studied by SEM. The solid state dye sensitized solar cell has been fabricated by using silane modified TiO 2 /PEO/PVdF-HFP polymer nanocomposites electrolyte and natural dye extracted from gross as a sensitizer. The current-voltage characteristics of solar cells showed an enhancement of open circuit voltage (V oc ) from 0.31 to 0.47 V and the best fill factor achieved about 64 %, when silane modified TiO 2 is added.

Solid state metal-free eosin-Y dye sensitized solar cell based on PVdF-HFP electrolytes: combined effect of surface modified TiO2 and plasticizer on electrochemical and photovoltaic properties

“…These factors cause the better ionic conductivity of silane modified TiO 2 hybrid polymer electrolyte systems. A similar behavior was observed in silanemodified PEO/PVdF and surface modified nano-TiO 2 blends by earlier reports [8,26,62]. The ionic conductivity decreases in both events with further addition of TiO 2 and modified TiO 2 nanoparticles.…”

“…The anions (iodide/triiodide) in the present electrolyte can easily move into the porous structures. In addition, highly charged surfaces of the nanoparticles add up as the conductive path [26].…”

“…4d) hinted that there may be interaction of K + in salt with TiO 2 in surface modified TiO 2 / PVDF-HFP electrolyte system sketched in Scheme 2, and a similar behavior was also reported. [8,26,67].…”

Solid state dye sensitized solar cells: Eosin-Y sensitized TiO2–ZnO/PEO–PVDF-HFP-MMT electrolytes/MWCNT–Nafion® counter electrode

“…The ionic conductivity of PEO/PVdF-HFP is increased with increasing the amount of modified MMT and reached optimum value of 1.6 ×10 -3 S/cm for 6 wt%. The incorporated MMT may influence the kinetics of polymer ϭϯ (PEO/PVDF-HFP) chains and promotes localized amorphous regions [18,31], which increase the ionic conductivity. When, the incorporated MMT exceeds optimum value (6 wt%) may decrease the amorphous content and slow the ionic transport property.…”

“…While it is blended with PVDF-HFP, crystallinity of is significantly reduced and obtained proper compatibility of through the interaction CF 2 group is present in PVDF-HFP and C-O-C in PEO [18].…”