Modification of sulfonated poly(ether ether ketone) membranes by impregnation with the ionic liquid 1‐butyl‐3‐methylimidazolium tetrafluoroborate for proton exchange membrane fuel cell applications

Abstract

Sulfonated poly(ether ether ketone) (SPEEK) membranes were modified by impregnation with the ionic liquid (IL) 1‐butyl‐3‐methylimidazolium tetrafluoroborate (BMI.BF4) by immersion into an IL aqueous solution for different periods of time. The modified membranes were investigated by thermogravimetric analyses (TGA), differential scanning calorimetry (DSC), ion exchange capacity (IEC), and conductivity. The SPEEK membrane immersed into the IL aqueous solution for 2 min showed greater dimensional and thermal stability than the pristine SPEEK membrane, and achieved higher decomposition temperatures. It also presented a higher conductivity value (1.0 mS cm−1), indicating that BMI.BF4 is a promoter of proton conductivity. The membrane electrode assembly (MEA) produced reached maximum values of power density of 0.13 W cm−2 and current density of 0.54 A cm−2 during fuel cell operation. The results indicate that the SPEEK membrane modified by immersion for 2 min is promising for use in a proton exchange membrane fuel cell. Its performance yielded values very close to those obtained with Nafion, which reaches maximum values of power density of 0.19 W cm−2 and current density of 0.77 A cm−2. POLYM. ENG. SCI. 56:1037–1044, 2016. © 2016 Society of Plastics Engineers

Transient Rechargeable Battery with a High Lithium Transport Number Cellulosic Separator

“…The good values arise from the combination of ions originating from the IL together with the charge carriers provided by the surface of CNCs as a result of ion‐exchange processes that yield conductivities even larger than Celgard soaked in aprotic electrolytes. [ 64 ] The electrochemical stability of the different membranes infused with Bmim‐TFSI is depicted in Figure 7b. The nature of the working electrode significantly influences the oxidation and reduction potentials of ILs.…”

Ionic Liquid–Poly(lactic acid) Blends as Green Polymer Electrolyte Membranes

“…48 The fuel cell performance of the PLA−[C 4 C 1 im][BF 4 ]20 membrane is indeed modest in comparison with state-of-theart perfluorinated acid membranes (from 20 mW cm −2 at 50 mA cm −2 to 510 mW cm −2 at 850 mA cm −2 ) 49 and with other bio-based membranes. 4,8,9,50 The relatively high ohmic resistance of the PLA−[C 4 C 1 im][BF 4 ]20 membrane in comparison with Nafion explains in part the huge difference, but the major problem is related to the poor electrode performance. Comparison with other biopolymer electrolytes is more favorable.…”

Synthesis and characterization of sulfonated polytriazoles utilizing 1,4‐bis(4‐azido‐2‐(trifluoromethyl)phenoxy)benzene for the proton exchange membrane applications

“…Subsequently cooling, the reaction mixture was precipitated in excess isopropanol (200 ml). Finally, the fibrous type polymer was obtained by washing the precipitated polymer with 20% aqueous ammonia, followed by distilled water numerous times, and vacuum dried at 100 C for 24 h. H NMR (DMSO-d 6 , ppm): 9.1-8.9 (1); 8.4-8.2 (11,15,20,25); 7.8-8 (23, 24); 6.9-7.4 (5,6,14,18); 5.12 (3), 1.6 (9).…”

“…The fuel cell (FC) is one of the essential energygenerating systems, which produces high-quality electricity from the fuels (mainly hydrogen, methanol, etc.) and oxygen without eliminating pollutants or noise [12][13][14][15] Proton exchange membrane fuel cells (PEMFCs) are modern energy renovation devices that directly convert the chemical energy of hydrogen into electricity with the advantages of high productivity, no emission, high power density, and low operating temperature. PEMFCs have been widely applied in transportation, 16 portable energy devices, 17 and stationary power plants 18 because of their excellent productivity and eco-friendliness.…”