Electrochemical Performance and Alkaline Stability of Cross-linked Quaternized Polyepichlorohydrin/PvDF Blends for Anion-Exchange Membrane Fuel Cells

Abstract

In the pursuit of good performing, low cost, and scalable anion exchange membranes (AEM), a series of blended electrolytes based on cross-linked quaternized Poly-epichlorohydrin (qPECH) and Polyvinylidene fluoride (PvDF) were prepared to evaluate their suitability for AEM fuel cells application. The thermomechanical and swelling analyses revealed the blending of these two macromolecules produces robust and heat-resistant microphase-segregated membranes with good dimensional stability. By varying the blend ratio, the ion exchange capacity (IEC) and transport properties of the resulting membrane can be easily adjusted and optimized with clear impact on its electrochemical performance. At 67:33 wt% blend ratio, high hydroxide conductivity (i.e. 56.3 mS cm -1 at 80 °C) and quite reasonable alkaline stability were achieved. The single H 2 -O 2 fuel cell using the qP-67 membrane yielded a beginning-of-life maximum power density of 32 mW cm -2 and an open circuit voltage (OCV) of 1.03 V at 50 °C without optimization.These preliminary results demonstrate the qPECH/PvDF blended membranes can be potentially applied in AEMFCs.

Semi-interpenetrating Polymer-Network Anion Exchange Membrane Based on Quaternized Polyepichlorohydrin and Polyvinyl Alcohol for Acid Recovery by Diffusion Dialysis

“…The W R of prepared sIPN AEMs increased with the content of ImPECH, the value was in the range of 14.29–168% (as shown in Figure ). The W R was influenced by hydrophilicity, while the hydrophilicity was proportional to the quantity of N -methylimidazole groups in the membrane matrix . With the increase of ImPECH content in the sIPN AEMs, the quantity of N -methylimidazole groups also followed an increasing trend because there were N -methylimidazole groups in the ImPECH polymer skeleton, and this eventually led to the gradual increase of hydrophilicity of membranes A–E.…”

The versatile, functional polyether, polyepichlorohydrin: History, synthesis, and applications

“…Several methods have been employed to create AEMs from PECH pre-cursors. Composite membranes formed from the combination of crosslinked PECH and fluorinated polymers like poly(vinylidene fluoride) (PVDF), 13,109 and poly(tetrafluoroethylene) (PTFE). [110][111][112] Interpenetrating networks (IPNs) of crosslinked PECH and another crosslinked polymer have also been used as AEMs.…”

“…Blended PECH and PVDF membranes used in anion exchange membrane fuel cell showed promising electrochemical properties despite its alkaline stability. 109 In all of these cases, the PECH used came from commercial sources and so is high M n , which is attractive for the AEMs. However, as synthetic techniques improve, high molecular weight copolymers of ECH with other functional epoxides can be produced which will add further opportunities for these materials as AEMs.…”

Communication—Electropolymerization of Anion-Conducting Polymer Films

“…[19][20][21][22] Ultra-thin anion-conducting films can be prepared by film-casting or grafting. 11,[23][24][25][26][27][28] However, the synthesis of anion-conducting polymer films of submicron thickness is challenging due to the restriction of their mechanical properties. [29][30][31][32] Interfacial polymerization is a well-known technique to form ultra-thin films; 33 however, it is hard to control the 2D morphology since it is not template-assisted.…”