Non-edible oil based polyurethane acrylate with tetrabutylammonium iodide gel polymer electrolytes for dye-sensitized solar cells

Polyurethane acrylate (PUA) gel polymer electrolytes were prepared with tetrabutylammonium iodide (TBAI) as the complex salt. Fourier transform infrared spectroscopy results confirmed that the N-H, C=O, C-N and C-O-C polar functional groups formed the coordination with TBA(+) cations of salt observed from the bands shift. The maximum ionic conductivity of (1.88 +/- 0.02) x 10(-4) S cm(-1) was obtained for the electrolyte with composition of 67.94 wt% PUA-30.00 wt% TBAI-2.06 wt% I-2 (S3 electrolyte) which influenced by the highest charge mobility of (6.24 +/- 0.12) x 10(-7) cm(2) V-1 s(-1) and number density of (1.93 +/- 0.04) x 10(21) cm(-3) estimated from fitting the Nyquist plots. The S3 electrolyte was electrochemically stable up to 1.64 V and capable of performing up to 2000 cycles steadily. Triiodide ion diffusivity obtained was 1.70 x 10(-8) cm(-2) s(-1). The electrolyte performance in dye-sensitized solar cells (DSSCs) was tested and cell with S3 electrolyte showed the highest solar conversion efficiency of (1.97 +/- 0.21)% with short-circuit current density (J(sc)) of (7.15 +/- 0.74) mA cm(-2) and open-circuit voltage (V-oc) of (0.55 +/- 0.01) V when exposed under 1000 W m(2) light illumination. The highest efficiency obtained was influenced by the high electrons driving force in DSSCs. Low reduction resistance (R-pt) of (2.46 +/- 0.08) Omega at the electrolyte/counter electrode interface along with low charge transfer resistance (R-ct) of (24.97 +/- 0.14) Omega at TiO2/dye/electrolyte interface and charge diffusion resistance (R-d) of (34.14 +/- 0.11) Omega in redox electrolyte increase the electrons dynamic, thus resulting high J(sc) and hence high DSSC efficiency. This work shows that PUA-based electrolytes have potential for DSSC applications.