Effective influences of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (EMIMTFSI) ionic liquid on the ion transport properties of micro-porous zinc-ion conducting poly (vinyl chloride) /poly (ethyl methacrylate) blend-based polymer electrolytes

Abstract

A series of new gel polymer electrolytes (GPEs) based on different concentrations of a hydrophobic ionic liquid (IL) 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (EMIMTFSI) entrapped in an optimized typical composition of polymer blend-salt matrix [poly(vinyl chloride) (PVC) (30 wt%) / poly(ethyl methacrylate) (PEMA) (70 wt%) : 30 wt% zinc triflate Zn(CF 3 SO 3 ) 2 ] has been prepared using facile solution casting technique. The AC impedance analysis has revealed the occurrence of the maximum ionic conductivity of 1.10 × 10 −4 Scm −1 at room temperature (301 K) exhibited by the PVC/PEMA-Zn(OTf) 2 system containing 80 wt% ionic liquid. The addition of EMIMTFSI into the optimized PVC/ PEMA-Zn(OTf) 2 system in different weight percentages enhances the number of free zinc ions thereby leading to enrichment of ionic conductivity. The structural and complexation behaviour of the as prepared polymer gel electrolytes was substantiated by subjecting these electrolyte films to X-ray diffraction (XRD) and Attenuated total reflectance -Fourier transformed infrared (ATR-FTIR) investigations. The wider electrochemical stability window~3.23 V and a reasonable cationic transference number (t Zn 2+ ) of 0.63 have been attained for the polymer gel electrolyte film containing higher loading of (80 wt%) ionic liquid. The development of the amorphous phase of these gel polymer electrolyte membranes with increasing ionic liquid content was observed from scanning electron microscopic (SEM) analysis. The results of the current work divulge the assurance of developing GPEs based on ionic liquids for prospective application in zinc battery systems.

Pursuit of reversible Zn electrochemistry: a time-honored challenge towards low-cost and green energy storage

“…Then, the authors evaluated the influence of [EMIM][TFSI] on this system and found that the weight ratio of [EMIM] [TFSI] in the electrolyte was positively correlated with the dielectric constant, amorphous phase ratio and ion conductivity. The highest ion conductivity could reach 0.11 mS cm −1 at room temperature 113,114 . Furthermore, the addition of nanosized SiO 2 in the electrolyte with an optimized composition effectively reduced T g and increased the thermal stability, electrochemical stability window (5.07 V) and ion conductivity (0.67 mS cm −1 ) at room temperature 82 .…”

“…The esterification of PAA triggers the coordination disruption between Zn 2+ and carboxylate radicals, paving a new route for their application in Zn 2+ transporting electrolytes. Suthanthiraraj and coworkers 82,113,114 thoroughly investigated polymer electrolytes based on poly (vinyl chloride) (PVC) and poly(ethyl methacrylate) (PEMA, Scheme 1) containing Zn(CF 3 SO 3 ) 2 as the dopant salt. First, the optimized weight ratio of the Zn salt was determined to be 30 wt% according to the thermal stability and electrochemical performance 114 .…”

Improved zinc ion transportation in gel polymer electrolyte upon the addition of nano-sized SnO2

“…On closer inspection, it may be clearly noted that the diffraction hump observed for filler-free gel polymer sample (Sn0) 15 in Figure 1(b) becomes relatively weaker, broader, as well as less significant 18 in all the gel composite complexes with the addition of ceramic nanofiller up to 3 wt%. This feature suggests the existence of possible Lewis acid–base interaction between the ether oxygen of the polymeric chain and Lewis acid sites of SnO 2.…”

“…To explore the perceptible changes in the structural characteristics of GPEs after the dispersion of nano-sized SnO 2 filler, XRD patterns of pure Zn(OTf) 2 salt, 15 filler-free gel sample Sn0, 15 pure SnO 2 nanofiller, and various specimens of PVC/PEMA-Zn(OTf) 2 -EMIMTFSI- x wt% SnO 2 (where x = 1, 2, 3, and 4, respectively) NCGPEs are displayed in Figure 1(a) and (b) and Figure 2(a) to (e). The intense diffraction peaks observed at 2 θ = 17.2°, 23.5°, 24.1°, 24.6°, and 29.8° in Figure 1(a) indicate the highly crystalline nature of Zn(OTf) 2 salt.…”

“…The intense diffraction peaks observed at 2 θ = 17.2°, 23.5°, 24.1°, 24.6°, and 29.8° in Figure 1(a) indicate the highly crystalline nature of Zn(OTf) 2 salt. 15 The XRD pattern of pure SnO 2 nanofiller exhibits prominent peaks at 2 θ = 26.6, 33.9, 37.9, 51.8, 54.8, 57.8, 61.9, 64.8, and 66° corresponding to (110), (101), (200), (211), (220), (002), (310), (112), and (301) diffraction planes, thus confirming the formation of rutile tetragonal structure 16,17 analogous with the Joint Committee on Powder Diffraction Standards’ data (card nos. 88-0287 and 41-1445).…”