Effect of lithium triflate salt concentration in methyl cellulose-based solid polymer electrolytes

Abstract

Solid polymer electrolytes (SPEs) film containing methyl cellulose (MC) serves as polymer host and lithium triflate (LiCF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) as a doping salt are prepared by solution cast technique. The complexation between polymer and salt are confirmed by FTIR spectral analysis. The Li <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> observed to form a coordination bond with the oxygen atom of the ether group (C-OC) at wave number 1051 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> to form Li <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> →OC <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> complexes. X-ray diffraction (XRD) spectral studies confirm addition of salt increased the amorphousness of the films consequences improve in ionic conductivity. The sample with 30 wt. % of LiCF <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> SO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> exhibited highest conductivity with the value of 2.1342 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-5</sup> Scm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-1</sup> at ambient temperature. The conductivity-temperature dependence studies showed that the conductivity of all samples seems to obey Arrhenius behavior and the conducting species are predominated by ions.