FTIR, thermal and ionic conductivity studies of nanocomposite polymer electrolytes

Abstract

In this study, proton-conducting nanocomposite plasticized polymer electrolytes based on poly(methyl methacrylate) (PMMA) complexed with trifluoromethanesulfonic acid (HCF3SO3) plasticized with propylene carbonate (PC) and dispersed with nanosized fumed silica (SiO2) have been prepared through the solution-casting technique. The ionic conductivity of electrolytes was measured as a function of acid, plasticizer and fumed silica concentrations. A maximum ionic conductivity of 3·31 × 10−4 S/cm for PMMA + 10 wt% trifluoromethanesulfonic acid polymer electrolytes and 5·37 × 10−3 S/cm for plasticized polymer electrolytes containing 50 wt% PC has been observed at room temperature. The viscosity percolation threshold for nanocomposite polymer electrolytes was observed at 3 wt% concentration of fumed silica with ionic conductivity of 8·84 × 10−3 S/cm at room temperature. Fourier transform infrared studies suggested the complexation of constituents of the electrolytes, formation of ion aggregates in unplasticized polymer electrolytes and dissociation of ion aggregates with the addition of the plasticizer in plasticized polymer electrolytes. Differential scanning calorimetry and thermogravimetric analysis studies proved that these electrolytes are thermally stable only up to 130°C. The conductivity shows negligible change with temperature from 30 to 130°C and time of 30 d, which is desirable for their use in practical applications such solid-state batteries, fuel cells, sensors and supercapacitors.

Theoretical Study of Nanocomposite Permittivity with a Tunable Clustering of Inclusions

“…[ 62–64 ] The strong increase in ionic conductivity of these electrolytes with the addition of plasticizers and nanoparticles is attributed to the formation of space‐charge layers and the dissociation of salt/ion aggregates. [ 65–69 ] The shape and orientation of the fillers, which strongly affect their percolation properties, can greatly facilitate ionic diffusion through newly formed ionic channels. [ 70,71 ] During the past three years, new opportunities for electroactive materials have started to emerge in optoelectronic applications, [ 72 ] photovoltaic applications, [ 73 ] and in the development of plasmonic biosensors and hyperbolic metamaterials.…”

Ion Transport Behavior in Nanotube‐Embedded Nanocomposite Polymer Electrolyte Membranes

“…A small oxidation peak appear at 0.5 V in cyclic voltagram “a,” which corresponds to NH 4 + /H + ion thereby indicating protonic conduction in NCPEs. [ 14 ] Further, on increasing MWCNT contents, the oxidation peak (related to NH 4 + /H + ) tends to diminish and finally disappears in cyclic voltagrams c & d peaks (indicated by arrows). This feature ascertains change in system morphology subsequent to MWCNT insertion in pristine electrolyte matrix.…”

Anhydrous proton-conducting imidazole triflate-SiO2 composite

“…These bands became smaller in 40ITF-60SiO 2 , 50ITF-50SiO 2 and disappeared in samples x ≥ 60, indicating the formation of core-shell structure. The absorption bands at 638, 1168, and 1284 cm −1 could be assigned to asymmetric bending, stretching, and symmetric stretching of SO 3 − of ITF [ 30 , 31 , 32 ]. The bands observed at 1058 and 1228 cm −1 were attributed to symmetric stretching of CF 3 - [ 30 , 31 , 33 ].…”

“…The absorption bands at 638, 1168, and 1284 cm −1 could be assigned to asymmetric bending, stretching, and symmetric stretching of SO 3 − of ITF [ 30 , 31 , 32 ]. The bands observed at 1058 and 1228 cm −1 were attributed to symmetric stretching of CF 3 - [ 30 , 31 , 33 ]. The bands at 515, 1030, and 1256 cm −1 corresponded to the CF 3 SO 3 − ···H + ion aggregates [ 32 , 33 ].…”