The role of glycerol in modulating ionic transport and electrochemical performance of PEO:NaCl solid polymer electrolytes

The article investigates the role of glycerol in modulating the ionic transport and electrochemical performance of polyethylene oxide (PEO):NaCl solid polymer electrolytes. It begins by addressing the limitations of conventional liquid electrolytes, such as leakage and flammability, and introduces solid polymer electrolytes (SPEs) as a promising alternative. The study focuses on PEO-based electrolytes, which are known for their ability to facilitate rapid ion transport through coordination with ether oxygens. However, the high crystallinity of PEO at ambient temperatures often results in poor ionic conductivity. The research explores the use of glycerol as a plasticizer to enhance conductivity by disrupting interchain hydrogen bonding and promoting ion dissociation and mobility. Experimental procedures involve the preparation of PEO:NaCl polymer films with varying glycerol concentrations, followed by electrochemical and non-electrochemical analyses, including X-ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The results demonstrate that the addition of glycerol significantly reduces the crystallinity of PEO, leading to improved ionic conductivity and dielectric properties. Electrochemical impedance spectroscopy (EIS) reveals that the highest ionic conductivity is achieved at a 32% glycerol concentration, highlighting the potential of glycerol-plasticized PEO:NaCl electrolytes for applications in solid-state electrochemical devices. The article concludes by emphasizing the importance of optimizing glycerol concentration to balance conductivity and mechanical stability, suggesting future work on long-term stability and scalability.