Biopolymers

Nanocomposite gel biopolymer electrolytes have been investigated for dye-sensitized solar cell applications by many researchers. In this work, hydroxypropyl cellulose (HPC), sodium iodide (NaI), 1-methyl-3-propylimidazolium iodide (MPII) as ionic liquid (IL), carbon nanotube (CNT), ethylene carbonate (EC) and propylene carbonate (PC) were used for preparation of non-volatile gel polymer electrolyte (GPE) system (HPC:EC:PC:NaI:MPII:CNT) for dye-sensitized solar cell application. Ethylene carbonate (EC) and propylene carbonate (PC) as plasticizer and iodine, I2 as redox mediator were used. The amounts of HPC, EC, PC, NaI and MPII were kept at 0.5, 5.0, 5.0, 0.5 and 0.5 g, respectively. The system were further incorporated with 1 wt.% of CNT with respect to the weight of HPC. GPEs were analyzed with electrochemical impedance spectroscopy (EIS). The ionic conductivity of 8.47×10−3 S cm−1 was achieved with introducing 1 wt.% of CNT. For DSSC fabrication, double-layer TiO2 paste was coated on FTO glass as photoactive electrode. Pt coated FTO glass was used as counter electrode. Photoactive electrode soaked in N719 dye for 24 hr. The gel polymer electrolytes were sandwiched between two anode and cathode electrodes for DSSC fabrication. The J-V characteristics of fabricated dye-sensitized solar cells were analyzed. The gel polymer electrolyte with 1 wt.% of CNT showed the energy conversion efficiency of 5.39 %, with short-circuit current density, open-circuit voltage and fill factor of 17.53 (mA cm−2), 440 (mV) and 69.9 %, respectively.