Abstract:
At present, energy consumption is rising predominantly, thus low cost, renewable, and
environmentally benign energy resources drag attraction extensively. Although many
researches have been done on polymer electrolytes, there is a captivating direction to
explore bio-polymer electrolytes in a quasi-solid state. In the present work, a novel gel
polymer electrolyte was prepared by a hot press method utilizing tetrapropylammonium
iodide (Pr4NI) and potassium iodide (KI) as the binary iodide salt system. Agar bio
polymer was combined with the glycerol and formaldehyde solvents to obtain the quasisolid state polymer plasticizer matrix. The KI and tetrapropylammonium iodide weight
ratio in the electrolyte was altered while keeping the masses of other ingredients constant
to optimize the solar cell performance. Gel electrolytes displayed quite high viscosity
while retaining a gel-like consistency at ambient temperature. Fourier transform infrared
spectroscopy results indicate a peak heightens gradually at 750 cm-1 with increasing Pr4NI
salt amount. Electrical impedance spectroscopy was used to deduce the ionic conductivity
of each electrolyte. The highest ionic conductivity of 3.39 mS cm−1 is achieved by the
electrolyte sample only with KI at 26 °C as the contribution for ionic conductivity from
small K+
cation is higher compared to the bulky Pr4N+
cation. The uniform shape of
cyclic voltammetry curves of each electrolyte during 12 consecutive cycles with 5 min
time steps revealed the stability of electrolytes. A dye-sensitized solar cell was assembled
by inserting the highest conducting gel polymer electrolyte having
Glass/FTO/TiO2/N719-Dye/GPE/Pt/Glass configuration. The dye-sensitized solar cell
fabricated with the highest conducting electrolyte displayed an efficiency of 0.36%
with JSC of 1.31 mA cm−2
, VOC of 0.4 V, and fill factor of 0.68.
Keywords: Biopolymer, Gel polymer electrolyte, Agar, Tetrapropylammonium iodide,
Dye-sensitized solar cell
