Acid–base blend membranes consisting of sulfonated poly(ether ether ketone) and 5-amino-benzotriazole tethered polysulfone for DMFC

Abstract

Low cost, acid-base blend membranes have been synthesized by blending sulfonated poly(ether ether ketone) (SPEEK) (an acid polymer) and various amounts of polysulfone tethered with 5-aminobenzotriazole (a basic polymer). The blend membranes have been characterized by ion-exchange capacity (IEC), liquid uptake, proton conductivity, methanol crossover, and fuel cell performance measurements. The blend membranes exhibit superior performance in direct methanol fuel cells (DMFC) compared to plain SPEEK and Nafion 115 membranes due to enhanced proton conductivity and much suppressed methanol crossover while preserving good swelling stability. The maximum power density of the blend membrane is two times higher than that of Nafion 115 membrane at 80 • C with 1 M methanol feed. Additionally, the effects of the size, pK a , and the number of nitrogen atoms of the tethered heterocycle groups on the properties of the blend membranes have also been investigated by comparing the properties of the blend membranes consisting of SPEEK and different basic polymers.

Building bridges: Crosslinking of sulfonated aromatic polymers—A review

“…Ionic crosslinks can also be achieved by casting mixed solutions of acid polymers and basic polymers or monomers (4,4-diaminodiphenylether) [141][142][143][144][145][146][147][148][149][150][151][152][153]. Acid polymers are for example SPEEK, SPES, SPPSU.…”

Enhanced properties of SPEEK with incorporating of PFSA and barium strontium titanate nanoparticles for application in DMFCs

“…This provides simple operation of DMFCs as compared with fuel cells that use gaseous hydrogen in feed . However, inadequate kinetics of methanol oxidation reaction in the anode, methanol crossover through the membranes, and poisoning effects of CO intermediates on the catalyst surface are three main challenges in the use of DMFC technology . The PEM is the crucial component in DMFCs that play an important role in fuel cell performance via an increase in proton conductivity as well as a barrier effect on methanol permeability .…”

Hydrogen bond cross-linked sulfonated poly(imino ether ether ketone) (PIEEK) for fuel cell membranes

“…Among the reported related blend membranes, the acid-base polymer blends showed many attractive properties. Manthiram and his colleagues reported series acid-base blend membranes, and the resulting blend membrane with number of nitrogen sites on N-base polymers and longer side chains showed low methanol crossover and good proton conductivity [24,25]. Kerres et al reported acid-base blend polymers based on SPEEK and N-base polymers.…”