Pre‐Oxidized Acrylic Fiber Reinforced Ferric Sulfophenyl Phosphate‐Doped Polybenzimidazole‐Based High‐Temperature Proton Exchange Membrane

Abstract

Pre-oxidized acrylic fiber (POAF) and ferric sulfophenyl phosphate (FeSPP) are incorporated into polybenzimidazole (PBI) membrane for the first time to prepare high-temperature proton exchange membranes (PEMs). The strong hydrogen bonds formed between PBI/POAF and FeSPP lead to good dispersion of POAF and FeSPP, facilitate the construction of proton channels, and enhance the dimensional and mechanical stability of the membranes. PBI/FeSPP (30 wt%) shows good proton conductivity (5.43 × 10 −2 and 4.13 × 10 −2 S cm −1 at 180 °C at 50% and 0 relative humidity (RH), respectively) and improved dimensional and mechanical stability compared with pristine PBI. By incorporating 5 wt% POAF into PBI/FeSPP (30 wt%), the swelling ratios are halved and the mechanical strength is enhanced by almost 30% while the proton conductivity is slightly affected (3.84 × 10 −2 and 2.97 × 10 −2 S cm −1 at 180 °C at 50% and 0 RH for PBI/FeSPP (30 wt%)/POAF (5 wt%), respectively). This work offers a new route in the preparation of high-temperature PEMs with enhanced properties.

Ionic Liquid Composite Polybenzimidazol Membranes for High Temperature PEMFC Applications

“…% IL–PBI composite membranes in the range of 4000–600 cm −1 . The pure PBI membrane showed a typical broad peak around 3500–3200 cm −1 attributed to the N–H stretching, and two bands at 1610 and 1423 cm −1 , which are associated with C=N and C–N stretching vibrations, respectively [48]. After incorporation of the IL in the polymer matrix, the presence of 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide in the membranes was confirmed by the presence of peaks at 1192 cm −1 (CF 3 stretching), 1591 cm −1 (SO 2 asymmetric stretching), 1131 cm −1 (SO 2 symmetric stretching), and 1052 cm −1 (S–N stretching) [49].…”

Anchoring Highly Sulfonated Hyperbranched PBI onto oPBI: Fast Proton Conduction with Low Leaching

“…This ensured sufficient proton donor-and-acceptors and their interconnectivity to accelerate proton transfer. The proton conductivity of oPBI-TAIC(10%)-SHBPBI(50%) at 180 °C and 0 RH (0.034 S cm –1 ) was higher than that of the reported HTPEMs, including mPBI-TGDDM(5%)/ZrSP(50%) (0.0186 S cm –1 ), PBI/FeSPP (30 wt %)/POAF (5 wt %) (0.0297 S cm –1 ), and oPBI/FeSPP (30 wt %)/GF (3 wt %) (0.024 S cm –1 ). ,, …”

“…The proton conductivity of oPBI-TAIC(10%)-SHBPBI(50%) at 180 °C and 0 RH (0.034 S cm −1 ) was higher than that of the reported HTPEMs, including mPBI-TGDDM(5%)/ZrSP(50%) (0.0186 S cm −1 ), PBI/FeSPP (30 wt %)/POAF (5 wt %) (0.0297 S cm −1 ), and oPBI/FeSPP (30 wt %)/GF (3 wt %) (0.024 S cm −1 ). 47,49,50 At each RH, the proton conductivity of oPBI-TAIC-SHBPBI membranes increased with temperature. The reliance was consistent with Arrhenius equation.…”

A Review of Recent Developments and Advanced Applications of High-Temperature Polymer Electrolyte Membranes for PEM Fuel Cells

“…Incorporating FeSPP in the PBI matrix as an insoluble proton conductor not only could provide a robust high-temperature proton conductivity but also improve the dimensional stability and the oxidative resistance of the resulting membrane. This was mainly because of achieving a better dispersion, the formation of more proton channels, and improved physicochemical properties due to building a hydrogen-bonding network between PBI and FeSPPP sites [173]. The composite and nanocomposite-based ionic liquid membranes listed in Table 2 are also considered as the PBI-based membranes with high protonic conductivity at anhydrous conditions (with a conductivity of about 370 mS.cm −1 at 180 • C) [139,151,174].…”