Chitosan polymer electrolytes doped with a dysprosium ionic liquid

In this work, we studied polymer electrolytes (PEs) that had the natural polymer chitosan as their matrix host. Different quantities of an ionic liquid that contains the lanthanide dysprosium as part of the anion, were incorporated in the chitosan matrix through the solvent casting method. The thermal, morphological and electrochemical properties of the membranes were accessed. The results, obtained by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), force microscopy (AFM), and complex impedance spectroscopy, revealed a minimum thermal stability of about 139 degrees C; a predominantly amorphous morphology combined with the presence of small crystalline domains and a satisfactory ionic conductivity. The sample with the highest ionic conductivity was the chitosan(1)[C(2)mim][Dy(SCN)(4)], (where 1 corresponds to the quotient between the mass of the polymer and the mass of the IL) which attained 6.76 x 10(-6) S(.)cm(-1) at 30 degrees C and 5.62 x 10(-4) S(.)cm(-1) at 100 degrees C. The results presented here suggest that these materials are promising and may find application in practical electrochemical devices.- The financial support of the Brazilian agencies Capes and CNPq is gratefully acknowledged as well as the support by Fundacao para a Ciencia e a Tecnologia (FCT/MCTES) in the Strategic Funding grant UID/QUI/0686/2019 and in the framework of the Research unit Associate Laboratory for Green Chemistry- LAQV which is financed by national funds (UID/QUI/50006/2019), grant SRFH/BD/90366/2012 (R.L.), and two contracts under Investigador FCT program (IF/00355/2012 - J.M.S.S.E. and IF/00621/2015 - P.M.R.)