“Evaporating” Graphene Oxide Sheets (GOSs) for Rolled up GOSs and Its Applications in Proton Exchange Membrane Fuel Cell

Abstract

In the present work, we prepare rolled up graphene oxide sheets (GOSs) by "evaporating" GOSs from their dispersion to a remote aluminum foil surface. The topological structure of the rolled up GOSs on the aluminum foil surface, which is determined by the quantity of the formed Al³⁺ ions from the reaction between the alumina on the aluminum foil surface and the weak acidic condensed vapor of the GOS dispersion, can be easily controlled via simply changing the H₂O content in the original GOS dispersion. Meanwhile, a GO/Nafion composite membrane for proton exchange membrane fuel cell is successfully prepared utilizing the as-obtained hole-like self-assembled structure of the rolled-up GOSs as a supporting material . The resultant composite membrane exhibits excellent proton conductivity compared to that of the recast Nafion membrane, especially under low-humidity conditions. An increase in proton conductivity by several times could be easily observed here, which is mainly attributed to the rearrangement of the microstructures of Nafion matrix to significantly facilitate the proton transport with rolled up GOSs being independently incorporated. The method reported here offers new degrees of freedom to achieve such transformations among the allotropic forms of carbon and/or develop new carbon material/polymer composite materials with excellent properties.

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

“…Table S1 (ESI †) summarized the various Naon based membrane performance results reported in literatures, for comparison with present study. 1,4,17,[56][57][58][59][60][61][62][63][64][65][66] Accordingly, the present study provides a novel Naon composite membrane with Fe 3 O 4 -SGO ller particles which helps to improve proton conductivity and reduce H 2 gas crossover. However, O 2 gas crossover from the cathode to the anode through PEM is a crucial drawback that leads to generation of H 2 O 2 and consequently membrane degradation.…”

Graphene Oxide Fuel Cell

“…10 The relatively high proton conductivity under these conditions suggests that GO paper could act as a proton electrolyte in various cells and batteries. [11][12][13][14][15][16] The proton conductivity of the GO paper is lower than that of the conventional Nafion electrolyte, which is usually used at high RH (∼100%), 17,18 while the overall conduction of the GO paper will be similar to that of Nafion if the GO paper is less than a tenth of the thickness of the Nafion.It has been reported that various gases do not pass through the GO paper, even when the GO is very thin (0.1 μm).19 This means thin GO paper is well suited as an electrolyte for the H 2 /O 2 fuel cell, because of the high proton conduction and the H 2 and O 2 gas shielding. Nafion electrolytes must be thick in order to achieve gas shielding (>10 2 μm).…”

Polymer fuel cell components modified by graphene: Electrodes, electrolytes and bipolar plates

“…The recast Nafion membrane presents a 78.14% decrease of proton conductivity at 30 1C-40% RH compared with that under 90 1C-40% RH, whereas GOS/Nafion membrane presents only 68.08% in the same condition. That is, as the authors suggested [88], because of better water retention of the composite membrane which also influenced the water uptake measurements (8.4% improvement).…”

“…proton conductive membranes. It can be used as a filler or additive to polymer matrix or it may even exist in the form of sheets or papers to be assembled during MEA fabrication [88][89][90][91][92][93][94]. Generally, Hummers' method (or its modification) is used to fabricate graphene for application to polymer electrolyte, but other techniques have also been applied as those described in Section 3.…”

“…Feng et al [88] investigated graphene oxide sheets (GOSs) Nafion composite membranes. In this work GOSs were prepared by a modified Hummers method and then rolled up with different topological structures through dissolving aluminium foil covering the GO layer.…”