Influence of the NiO nanoparticles on the ionic conductivity of the agar-based electrolyte

NiO nanoparticles with an average size of 15 nm were prepared by a simple, reproducible and low-cost controlled method, using nickel nitrate hexahydrate (Ni(NO3)2·6H2O). These nanoparticles were added to an agar-based polymer electrolyte formula, resulting, after reflux and solution casting, in a proton conducting membrane. The highest ionic conductivity values of 5.19x10-5 S cm-1 at room temperature and 3.32x10-4 S cm-1 at 80 ºC, were obtained for the sample with 50 wt. % of acetic acid and 0.25 g of NiO. Moreover, the samples showed 75 % of transparency in the visible region, a homogeneous...