Electrochemical Characteristics of Glycerolized PEO-Based Polymer Electrolytes

Muhammad S Mustafa; Hewa O Ghareeb; Shujahadeen B Aziz; M A Brza; Shakhawan Al-Zangana; Jihad M Hadi; M F Z Kadir

doi:10.3390/membranes10060116

Electrochemical Characteristics of Glycerolized PEO-Based Polymer Electrolytes

Membranes (Basel). 2020 Jun 5;10(6):116. doi: 10.3390/membranes10060116.

Authors

Muhammad S Mustafa¹, Hewa O Ghareeb¹, Shujahadeen B Aziz^{2

3}, M A Brza^{2

4}, Shakhawan Al-Zangana⁵, Jihad M Hadi^{6

7}, M F Z Kadir⁸

Affiliations

¹ Department of Chemistry, College of Science, University of Sulaimani, Qlyasan Street, Sulaimani 46001, Iraq.
² Hameed majid Advanced Polymeric Materials Research Lab., Physics, College of Science, University of Sulaimani, Qlyasan Street, Sulaimani 46001, Iraq.
³ Department of Civil Engineering, College of Engineering, Komar University of Science and Technology, Sulaimani 46001, Iraq.
⁴ Manufacturing and Materials Engineering Department, Faculty of Engineering, International Islamic University of Malaysia, Kuala Lumpur 50603, Malaysia.
⁵ Department of Physics, College of Education, University of Garmian, Kalar 46021, Iraq.
⁶ Kurdistan Technical Institute, Sulaimani 46001, Iraq.
⁷ College of Engineering, Tishk International University, Sulaimani 46001, Iraq.
⁸ Centre for Foundation Studies in Science, University of Malaya, Kuala Lumpur 50603, Malaysia.

Abstract

In this article, poly(ethylene oxide)-based polymer electrolyte films doped with ammonium iodide (NH₄I) and plasticized with glycerol were provided by a solution casting method. In the unplasticized system, the maximum ionic conductivity of 3.96 × 10-5 S cm^-1 was achieved by the electrolyte comprised of 70 wt. % PEO:30 wt. % NH₄I. The conductivity was further enhanced up to (1.77×10-4 S cm^-1) for the plasticized system when 10 wt. % glycerol was added to the highest conducting unplasticized one at ambient temperature. The films were characterized by various techniques to evaluate their electrochemical performance. The results of impedance spectroscopy revealed that bulk resistance (R_b) considerably decreased for the highest plasticized polymer electrolyte. The dielectric properties and electric modulus parameters were studied in detail. The LSV analysis verified that the plasticized system can be used in energy storage devices with electrochemical stability up to 1.09 V and the TNM data elucidated that the ions were the main charge carrier. The values of the ion transference number (t_ion) and electron transfer number (t_el) were calculated. The nonappearance of any redox peaks in the cyclic voltammograms indicated that the chemical reaction had not occurred at the electrode/electrolyte interface.

Keywords: EDLC and CV; LSV and TNM; dielectric properties; electric modulus study; glycerolized PEO electrolyte; impedance.