Preparation and characterization of starch-ammonium nitrate polymer electrolyte

Abstract

A proton-conducting polymer electrolyte system based on starch doped ammonium nitrate �N03) has been prepared through solution casting method. The ionic conductivity for the starch- NH4N03 was conducted over a wide range of frequency between 50Hz and 1MHz and at temperatures between 303K and 37 3K. Fourier Transform Infrared (FTIR) spectroscopy showed that the complexation has occurred. The sample containing 25wt% ammonium nitrate exhibit the highest conductivity at room temperature at 2. I 9x10- 6 S·cm- 1 for sample SAN25 studied using Electrochemical Impedance Spectroscopy (EIS). The conductivity by various temperatures obey Arrhenian rule and found to influence the proton conduction. Calculations using the Rice and Roth model provide number of mobile ions, 17, diffusion coefficient, D and ionic mobility,µ. The transport parameter of the samples shows that the increase in conductivity is due to the increase in the mobility of ions, diffusion coefficient where the value of the cation diffusion coefficient, D+ at 5.99xl011

cm 2 s- 1 obtained is higher than the value of the cation diffusion coefficient, 12 D_ at l.70xl0- 2 1 and the value of the cation ionic mobility,µ+ at 2.29xI0- cm s- 09 cm 2 Y- 1 s1 is higher than the value of the anion ionic mobility,µ_ at 7.08x 1011

cm 2 Y- 1 s- 1 .The Transference Number Measurement was performed to correlate the diffusion phenomena to the conductivity, a behaviour of starch-NH4N03 polymer electrolyte. Therefore, this study had proven that the starch-ammonium nitrate polymer electrolyte is a proton conductor.