Novel nanocomposite membranes based on blended sulfonated poly(ether ether ketone)/poly(vinyl alcohol) containing sulfonated graphene oxide/Fe₃O₄ nanosheets for DMFC applications

Abstract

In this study, the Sulfonated graphene oxide (SGO)/Fe 3 O 4 nanosheets were synthesized by hydrothermal method and incorporated into blend sulfonated poly(ether ether ketone) (SPEEK)/poly(vinyl alchole) (PVA) matrix with different weight percent of (SGO)/Fe 3 O 4 nanosheets. The performances of prepared membranes were investigated by water uptake, membrane swelling, mechanical and thermal stability, proton conductivity, methanol permeability and DMFC test. It was found that the water uptake and tensile strength of SPEEK membrane increased and proton conductivity and power density decreased by 2 blending with PVA. Incorporation of SGO/Fe 3 O 4 nanosheets into SPEEK/PVA matrix enhanced mechanical stability, proton conductivity and methanol barrier properties of membrane. The SPEEK/PVA/SGO/Fe 3 O 4 nanocomposite membrane with optimal nanosheets content (5 wt%) exhibits low methanol permeability (8.83 × 10 −7 cm 2 s -1 ), high tensile strength (51.2 MPa), high proton conductivity (0.084 S cm -1 at 25°C) and high power density (122.7 mW cm -2 at 80°C) and suggests its potential application in DMFCs.

Sulfonated graphene oxide/Nafion composite membranes for high temperature and low humidity proton exchange membrane fuel cells

“…Again the existence of Fe 3 O 4 into the polymer matrix is a problem that facilitates the oxidative degradation of PEM when combined with hydroxyl (OHc) and hydroperoxyl (OOHc) radicals formed in cathode during PEMFC operation. Recently, Beydaghi et al 9 reported that the addition of 5 wt% Fe 3 O 4 -SGO could increase the durability of SPEEK/PVA blend signicantly. During 120 h of operation, the fuel cell equipped with Fe 3 O 4 -SGO/SPEEK/PVA membrane showed a OCV reduction of 0.…”

“…1,9 Besides, Naon membrane exhibits high hydrogen permeability denoted to as high hydrogen crossover from the anode to cathode through PEM as a result of concentration gradient. 10,11 Accordingly, researchers are developing modied PFSA membranes or designing alternative PEMs.…”

A Nafion-Ceria Composite Membrane Electrolyte for Reduced Methanol Crossover in Direct Methanol Fuel Cells

“…However, the water uptake decreased when the content of CeO 2 is more than 1 wt. %, probably due to the aggregation of oxide filler in the composite membrane [27]. Table 1.…”

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

“…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 . Additionally, the polymeric membrane should have desired properties such as suitable thermal, mechanical, and chemical stability; low cost; and easy film forming .…”