Corrigendum to “Synthesis and testing of a composite membrane based on sulfonated polyphenylene oxide and silica compounds as proton exchange membrane for PEM fuel cells” Mater. Res. Bull., 96, (December (Part 3)), (2017), 136–142 (original) (raw)
Related papers
Materials Research Bulletin, 2017
The present work is an attempt to improve the usseful properties of sulfonated polyphenylene oxide in order to obtain a proton exchange membrane (PEM) for proton exchange membrane fuel cells(PEMFC). Formation of siloxane compounds inside the polymer matrix through an in situ sol-gel process improves properties of the composite membrane: water retention, tensile strength and dimensional stability of the membrane. The presence of the silicone atoms inside the polymer matrix is highlited in the X-ray fluorescence spectra. Parameters related to water absorbtion and proton transport inside the membrane such as: water uptake, hydration number (l), dimensional expansion by hydration, ion exchange capacity and sulfonation degree show an optimization of the composite membrane compared to the polymeric one. Furthermore, the tensile strength of the composite membranes is better than the polymeric one when both samples are fully hydrated.
Review of the proton exchange membranes for fuel cell applications
International Journal of Hydrogen Energy, 2010
Proton-exchange membrane fuel cells (PEMFCs) are considered to be a promising technology for clean and efficient power generation in the twenty-first century. Proton exchange membranes (PEMs) are the key components in fuel cell system. The researchers have focused to reach the proton exchange membrane with high proton conductivity, low electronic conductivity, low permeability to fuel, low electroosmotic drag coefficient, good chemical/thermal stability, good mechanical properties and low cost. These are classified into the "iron triangle" of performance, durability, and cost. Current PEMFC technology is based on expensive perflourinated proton-exchange membranes (PEMs) that operate effectively only under fully hydrated conditions. There is considerable application-driven interest in lowering the membrane cost and extending the operating window of PEMs. PEMFC system complexity could be reduced by the development of 'water-free' electrolytes that do not require hydration. It also enables the PEMFC to be operated under 'warm' conditions (i.e. above 100 C) thus further improving its efficiency. Capital cost could also be further reduced because at warmer conditions less Pt could be used. This paper presents an overview of the key requirements for the proton exchange membranes (PEM) used in fuel cell applications, along with a description of the membrane materials currently being used and their ability to meet these requirements. A number of possible alternative candidates are reviewed and presented in this paper. Also discussed are some of the new materials, technologies, and research directions being pursued to try to meet the demanding performance and durability needs of the PEM fuel cell industry. The alternative PEMs are classified into three categories: (1) modified Nafion Ò composite membranes; (2) functionalized non-fluorinated membranes and composite membranes therein; and (3) acidebase composite membranes. Several commonly used inorganic additives are reviewed in the context of composite membranes. Finally, the general methods of the measuring and evaluating of proton exchange membrane properties have been investigated such as proton conductivity, ion exchange capacity, water uptake, gas permeability, methanol permeability, durability, thermal stability and fuel cell performance test.
Ion exchange resin/polystyrene sulfonate composite membranes for PEM fuel cells
Journal of Membrane Science, 2004
A new composite proton exchange membrane was made by casting a polystyrene sulfonate (PSS) solution with suspended micron sized particles of a crosslinked PSS ion exchange resin. The chemical compatibility of the resin and the PSS allow stable composites with up to 50 wt.% resin. The resin/PSS composite membranes have greater ion exchange capacity than PSS membranes, but the ion conductivity is similar to that of PSS. Swelling of the composite membranes as a function of water uptake is lower than that of PSS. The composite membranes are mechanically more robust and display greater chemical stability in a fuel cell than the PSS membranes. The polarization curves show long-term degradation of the membranes; the cell potential decreased by 60% in 55 h for a PSS membrane, and in 340 h for a composite membrane. The reduced rate of degradation of the composite membranes suggests that with further refinement they may have potential as an inexpensive alternative for PEM fuel cells.
The Development of New Membranes for Proton Exchange Membrane Fuel Cells
ECS Transactions, 2007
Recent work at 3M has focused on the development of solvent cast proton exchange membranes (PEM's) for use in PEM fuel cells. These new membranes are a perfluorinated sulfonic acids based on a low molecular weight perfluorinated monomer and they exhibit excellent mechanical properties and chemical stability and high ionic conductivity. The low molecular weight of the monomer allows membranes with equivalent weight as low as 800 g/mole to have good mechanical properties when hydrated. Stabilizing additives in these membranes have been shown to improve the oxidative stability in Fenton's tests. Physical property, conductivity and fuel cell tests have been performed. When incorporated into membrane electrode assemblies, these new membranes have provided excellent performance and a greater than 15-fold increase in durability under accelerated fuel cell test conditions, compared with similar commercial PEM's.
SPEEK and SPPO Blended Membranes for Proton Exchange Membrane Fuel Cells
Membranes, 2022
In fuel cell applications, the proton exchange membrane (PEM) is the major component where the balance among dimensional stability, proton conductivity, and durability is a long-term trail. In this research, a series of blended SPEEK/SPPO membranes were designed by varying the amounts of sulfonated poly(ether ether ketone) (SPEEK) into sulfonated poly(phenylene) oxide (SPPO) for fuel cell application. Fourier transform infrared spectroscopy (FTIR) was used to confirm the successful synthesis of the blended membranes. Morphological features of the fabricated membranes were characterized by using scanning electron microscopy (SEM). Results showed that these membranes exhibited homogeneous structures. The fabricated blended membranes SPEEK/SPPO showed ion exchange capacity (IEC) of 1.23 to 2.0 mmol/g, water uptake (WR) of 22.92 to 64.57% and membrane swelling (MS) of 7.53 to 25.49%. The proton conductivity of these blended membranes was measured at different temperature. The proton con...
Chemically Crosslinked Sulfonated Polyphenylsulfone (CSPPSU) Membranes for PEM Fuel Cells
Membranes
Sulfonated polyphenylsulfone (SPPSU) with a high ion exchange capacity (IEC) was synthesized using commercially available polyphenylsulfone (PPSU), and a large-area (16 × 18 cm2) crosslinked sulfonated polyphenylsulfone (CSPPSU) membrane was prepared. In addition, we developed an activation process in which the membrane was treated with alkaline and acidic solutions to remove sulfur dioxide (SO2), which forms as a byproduct during heat treatment. CSPPSU membranes obtained using this activation method had high thermal, mechanical and chemical stabilities. In I-ViR free studies for fuel cell evaluation, high performances similar to those using Nafion were obtained. In addition, from the hydrogen (H2) gas crossover characteristics, the durability is much better than that of a Nafion212 membrane. In the studies evaluating the long-term stabilities by using a constant current method, a stability of 4000 h was obtained for the first time. These results indicate that the CSPPSU membrane ob...
Sulfonated poly (arylene ether sulfone) proton exchange membranes for fuel cell applications
Green Processing and Synthesis, 2015
Sulfonated poly (arylene ether sulfone) membranes were synthesized by direct copolymerization of 4,4-bis (4-hydroxyphenyl) valeric acid, 4,4′-difluorodiphenyl sulfone and synthesized sulfonated 6F-bisphenol-A/ bisphenol-A as novel proton exchange membranes for fuel cell applications. Prepared membranes were subsequently crosslinked with synthesized 6F-bisphenol-A based epoxy resin (EFN) by thermal curing reaction keeping in view the resilience and toughness of the membranes. The structural characterization was done by using Fourier transform infrared (FTIR), 1 H nuclear magnetic resonance (NMR) and 13 C NMR techniques. Proton conductivity of the membranes was determined by a four-point probe technique. Methanol permeability was determined by using a diffusion cell in which concentration of the liquids was determined by UV-spectroscopic technique. The enhancement in mechanical properties determined by a universal testing machine and also a better oxidative stability were observed for the crosslinked membranes. However, a decrease in their water and methanol absorption, ion exchange capacity, proton conductivity and methanol permeability was observed. This was due to the reduction in the numbers of ionic channels in case of crosslinked membranes which was confirmed by carrying out morphological analysis of the membranes using atomic force microscopy. In addition, X-ray diffraction measurement by XPERT-PRO diffractometer was also used for structural characterization. Crosslinked membranes showed better thermal stability as determined by thermogravimetric analysis and differential scanning calorimetry.
Development and characterization of novel composite membranes for fuel cell applications
Journal of Materials Chemistry A, 2013
In this paper, we report a novel composite electrolyte membrane consisting of a polyethylene substrate and a Nafion ionomer. Polymer Electrolyte Membranes (PEMs) have been gaining increasing attention in the fuel cell industry due to their excellent proton conductivity and among them the Nafion membrane is by far the most widely used membrane electrolyte. However, it suffers from several drawbacks such as high fuel crossover and low mechanical strength, which lower the fuel cell performance and disturb the structural integrity. In order to deal with these problems, we have prepared a pore filling membrane that is composed of a porous substrate and a filling electrolyte. Nafion was used as a filling electrolyte and was impregnated into the pores of the porous substrate made up of ultra-high molecular weight polyethylene (UHMWPE). The UHMWPE backbone serves as a structural support and blocks the fuel crossover while the impregnated Nafion molecules provide the proton conducting path. A porous UHMWPE membrane with a porosity of approximately 66% was prepared, and the Nafion electrolyte was impregnated into the pores so that an NPE (Nafion-polyethylene composite) membrane was formed. Major accomplishments of this work are (a) the membrane is biaxially oriented and has higher tensile strength and modulus especially under wet conditions as well as better electrolyte conductivity because the resistivity in the system is reduced due to the development of a very thin (13 mm) film composite, and (b) the electrolytic membrane is economical because of the utilization of a lesser amount of ionomer. Systematic characterization of both porous polyethylene and the NPE composite has been performed using SEM, EDAX, XRD, XRF, porosity measurement, tensile tests, proton conductivity, and fuel cell performance tests.
Challenges for PEM fuel cell membranes
International Journal of Energy Research, 2005
Proton Exchange Membrane (PEM) fuel cells have been developed extensively since their introduction over thirty years ago. A key component, the polymer electrolyte membrane, acts as both a separator and an electrolyte in the operating fuel cell. Composite membranes offer the capability of using a wide variety of ionomeric polymers that may be mechanically too weak to use as freestanding films. These thinner membranes can replace thicker non-reinforced membranes, thereby increasing performance while simultaneously increasing durability. However, additional advancements will be necessary to meet aggressive operating conditions of higher temperatures and/or lower humidities, as well as longer operating lifetimes demanded in both stationary and automotive applications. In this paper, these challenges for fuel cell membranes are considered.