Nanocomposite Proton Exchange Membranes Research Articles

Proton Exchange Membranes from Sulfonated Lignin Nanocomposites for Redox Flow Battery Applications.

Redox flow batteries (RFBs) are increasingly being considered for a wide range of energy storage applications, and such devices rely on proton exchange membranes (PEMs) to function. PEMs are high-cost, petroleum-derived polymers that often possess limited durability, variable electrochemical performance, and are linked to discharge of perfluorinated compounds. Alternative PEMs that utilize biobased materials, including lignin and sulfonated lignin (SL), low-cost byproducts of the wood pulping process, have struggled to balance electrochemical performance with dimensional stability. Herein, SL nanoparticles are demonstrated for use as a nature-derived, ion-conducting PEM material. SL nanoparticles (NanoSLs) can be synthesized for increased surface area, uniformity, and miscibility compared with macrosized lignin, improving proton conductivity. After addition of polyvinyl alcohol (PVOH) as a structural backbone, membranes with the highest NanoSL concentration demonstrated an ion exchange capacity of 1.26 meqg-1, above that of the commercial PEM Nafion 112 (0.98 meqg-1), along with a conductivity of 80.4 mScm-1 in situ, above that of many biocomposite PEMs, and a coulombic efficiency (CE), energy efficiency (EE) and voltage efficiency (VE) of 91%, 68% and 78%, respectively at 20mAcm-2. These nanocomposite PEMs demonstrate the potential for valorization of forest biomass waste streams for high value clean energy applications.

Supramolecular complexation of metal oxide clusters in PVDF-PVP blends for large scale fabrication of proton exchange membranes for fuel cells

The perfluorosulfonic acid (PFSA) polymers have achieved great success as proton exchange membranes (PEMs) in various energy storage and conversion devices; nevertheless, the improvements regarding PEMs' synthetic cost, mechanical properties, stability and processability are still urgently required. Herein, 1 nm super acidic metal oxide cluster, H3PW12O40 (PW12), is complexed with the blends of polyvinylpyrrolidone (PVP) and polyvinylidene fluoride (PVDF) to afford nanocomposite PEMs that enables the stable and effective operation of hydrogen fuel cell devices. As the polymer matrix, the PVDF is blended with PVP via inter-chain hydrogen bonding to provide mechanical support for the nanocomposite PEMs. The further introduced PW12 clusters can interact strongly with PVP via electrostatic attraction to enhance the PEMs' mechanical strength (E = 231 MPa) and prevent the leaching of PW12 for long-term stability. Meanwhile, the incorporation of the super acidic PW12 can facilitate the fast proton transportation and therefore, lead to the significant increasement of proton conductivity to 9.8 × 10−3 S cm−1 at 70 °C and 100% RH. Due to the excellent mechanical properties and the supramolecular interaction among the components, the PEMs’ thickness can be controlled to be challenging ∼10μm for feasible large-scale continuous processing. Finally, the molecular design enables the successful fabrication of the nanocomposite PEMs into fuel cell devices with the power density as 342.8 mW cm−2. The studies not only shed light on the structure-properties of polymer nanocomposites, but also pave avenues to the design of robust composite PEMs for fuel cell appliacations.

Polynorepinephrine-regulated filler sulfonation toward interfacial reformation and conductive promotion of nanocomposite proton exchange membrane

Interfacial compatibility between filler and matrix substantially affects the overall morphology and performance of nanocomposites. Compared with bare montmorillonite (MMT), surface modified product such as sulfonated MMT (SMMT) has been known to render optimized interfacial compatibility in composite proton exchange membranes (PEMs) for proton exchange membrane fuel cells (PEMFCs) and direct methanol fuel cells (DMFCs). Nevertheless, in-depth understanding and investigation on the sulfonation of MMT are seldom focused, such as uniformity and sufficiency. Herein, these broadly neglected issues are proposed and resolved using an exemplary polynorepinephrine (PNE)-regulated SMMT (SNMMT). Rather than direct sulfonation utilizing the inherent hydroxyl groups of MMT, a PNE coating with ample hydroxyl groups is deposited on MMT beforehand, which results in more homogeneous and sufficient sulfonation of SNMMT. Compared with normal SMMT, this alteration on surficial geography of filler functionalization brings significant benefits when composited with Nafion matrix, including harmonized filler-matrix compatibility, improved mechanical stability and enhanced proton conduction. Moreover, the antioxidative ability of PNE layer enables improved chemical stability of nanocomposite PEM. The Nafion/SNMMT composite PEM achieves 0.275 S cm−1 proton conductivity at 95 °C in water, evidently beyond any previously reported composite PEMs using normal SMMT. Equipped with this reformed nanocomposite PEM, both PEMFC and DMFC display competitive peak power densities (1.121 W cm−2 with H2/O2 at 80 °C/100 % relative humidity (RH) for PEMFC, and 0.228 W cm−2 with 1.6 M methanol/100 % RH O2 for DMFC), and simultaneously show minor performance deteriorations in constant current density operation and RH cycle tests. It would be instructive the specific focus and reformation on the uniformity and sufficiency of filler modification may render significant interface and performance advancements for nanocomposites.

Carboxyl-functionalized nanocellulose/sulfonated poly(aryl ether ether ketone ketone) composites for proton exchange membrane by electrospinning

A novel nanocomposite proton-exchange membrane (PEM) was obtained by combined electrospinning and solution casting of a composite solution of sulfophenylated poly(ether ether ketone ketone) (SP-PEEKK) and maleic anhydride modified nanocellulose (MN). SP-PEEKK was prepared by polymerization between phenyl hydroquinone and 1,4-bis(4-fluorobenzoyl)benzene followed by post-sulfonation. Nanocellulose (NCC) was prepared by the acid treatment of MCC with sulfuric acid, and MN with carboxyl group was obtained by modifying NCC with maleic anhydride. PEMs with 2% MN (MN2) showed a water uptake of 28% at 100°C, which was higher than that of MN0 (with 0% MN content). MN2 possessed a high tensile strength of 48.7 MPa, Young’s modulus of 1.3 GPa, and elongation at break of 34%, which was 54%, 21%, and 16% higher than those of MN0, respectively. Thus, the ordered distributed of MN was illustrated to be the effective reinforcing material for SP-PEEKK membranes because of the strong interface between the hydroxyl group of rigid MN and the sulfonic acid group of SP-PEEKK. MN2 also had a substantially higher proton conductivity of 0.09 S cm−1 at 90°C than MN0 (0.037 S cm−1). Therefore, combined electrospinning and solution casting was found to be a promising choice to improve the proton conductivity of nanocomposite PEMs, as promoted by the three-dimensional hydrogen bond-proton-transport network formed by the well-oriented MN in SPEEKK produced by the electrospinning.

High performance nanocomposite proton exchange membranes based on the nanohybrids formed by chemically bonding phosphotungstic acid with covalent organic frameworks

The performance deterioration of the proton exchange membranes (PEMs) under low humidity is one of the key issues hindering the further development of PEM fuel cells (PEMFCs). Covalent organic frameworks (COFs) offer the possibility of facilitating proton transport due to their structural advantages such as ordered pore networks and tunable functionalities. In this work, we have applied a hydrothermal method to synthesize the phosphotungstic acid (HPW) functionalized covalent organic framework (COF) nanohybrids (P–COF), in which the HPW is immobilized within the cavities of COF through the chemical bonds. The strong acidity of HPW and the ordered structure of P–COF facilitates the fast and efficient proton conduction in the Nafion/P–COF nanocomposite membranes, resulting in superior proton conductivity along with outstanding performance in H2/O2 PEMFCs under low humidity. At 25 °C under 55% RH, the proton conductivity of Nafion nanocomposite membrane with 4 wt% P–COF (Nafion/P–COF-4) reaches a proton conductivity of 0.061 S cm−1, which is 307% higher than that of the recast Nafion. The membrane electrode assembly (MEA) based on Nafion/P–COF-4 membrane exhibits excellent performance in a H2/O2 fuel cell, achieving the peak power density of 724 mW cm−2 at 80 °C and 50% RH, 138% higher than the MEA based on the recast Nafion.

Nanocomposite proton exchange membranes based on sulfonated polyethersulfone and functionalized quantum dots for fuel cell application

In this work novel nanocomposite proton exchange membranes were prepared using sulfonated polyethersulfone (SPES) with incorporation of ZnS functionalized quantum dots (FQDs) with a solution-casting method. The effect of functionalized groups (–COOH and NH2) of ZnS FQDs on the SPES membrane properties such as proton conductivity and performance was investigated. The highest proton conductivity of the nanocomposite membranes was achieved 116 mS/cm at 90°C. The nanocomposite membranes containing 2 wt% of ZnS FQDs displayed constant proton conductivity life time in 180 hours and fuel cell life time in 70 hours at 90°C, 98% RH, which confirmed strong interaction between functionalized group of ZnS FQDs and –SO3H groups of SPES. The power density of the SPES-ZnS FQDs nanocomposite membranes (DS of SPES: 45% and ZnS FQDs content: 2 wt%) obtained 0.53 W/cm2 in 98% RH, 0.5 V, and 90°C. The results confirmed that the prepared nanocomposite membranes with remarkable performance can be used as useful membranes for fuel cells.

High Performance and Self-Humidifying of Novel Cross-Linked and Nanocomposite Proton Exchange Membranes Based on Sulfonated Polysulfone.

The introduction of inorganic additive or nanoparticles into fluorine-free proton exchange membranes (PEMs) can improve proton conductivity and have considerable effects on the performance of polymer electrolyte membrane fuel cells. Based on the sol–gel method and in situ polycondensation, novel cross-linked PEM and nanocomposite PEMs based on a sulfonated polysulfone (SPSU) matrix were prepared by introducing graphene oxide (GO) polymeric brushes and incorporating Pt-TiO2 nanoparticles into an SPSU matrix, respectively. The results showed that the incorporation of Pt-TiO2 nanoparticles could obviously enhance self-humidifying and thermal stability. In addition, GO polymer brushes fixed on polymeric PEM by forming a cross-linked network structure could not only solve the leakage of inorganic additives during use and compatibility problem with organic polymers, but also significantly improve proton conductivity and reduce methanol permeability of the nanocomposite PEM. Proton conductivity, water uptake and methanol permeability of the nanocomposite PEM can be up to 6.93 mS cm−1, 46.58% and be as low as 1.4157 × 10−6 cm2 s−1, respectively, which represent increases of about 70%, about 22% and a decrease of about 40%, respectively, compared with that of primary SPSU. Therefore, the synergic action of the covalent cross-linking, GO polymer brush and nanoparticles can significantly and simultaneously improve the overall performance of the composite PEM.

Enhanced performance of novel carbon nanotubes - sulfonated poly ether ether ketone (speek) composite proton exchange membrane in mfc application

Sulfonated poly ether ether ketone (SPEEK) nanocomposite proton exchange membrane (PEM) was prepared by incorporating multi-walled carbon nanotubes (CNT) at different weight percentages for microbial fuel cell (MFC) applications. Physico-chemical, thermal, mechanical and morphological characteristics of the prepared CNT-SPEEK composite membranes were analyzed using various techniques. Further, the water uptake capacity, Ion exchange capacity (IEC) and MFC performance of the CNT-SPEEK composite membranes were evaluated and compared with the pristine SPEEK membrane. Results show that incorporation of CNTs in SPEEK membranes exhibited a better water uptake capacity (34.18%–36.02%) and IEC (1.94–2.15 meq/g) compared to the SPEEK membrane. Improvement in membrane properties resulted in 2-fold higher power density compared to SPEEK membrane. Composite membrane with 0.75% CNT-SPEEK produced the higher power density (1.77 W/m2) in comparison with all the membranes evaluated. Chemical oxygen demand (COD) removal efficiency values of the MFC with SPEEK composite membranes were also found to be around 90%. Overall, the results reveal that CNT-SPEEK composite membrane as a potential PEM for MFC applications.

High Performance Nanocomposite Proton Exchange Membranes Based on the Nanohybrids Formed by Chemically Bonding Phosphotungstic Acid with Covalent Organic Frameworks

High Performance Nanocomposite Proton Exchange Membranes Based on the Nanohybrids Formed by Chemically Bonding Phosphotungstic Acid with Covalent Organic Frameworks

Surface initiated RAFT polymerization to synthesize N-heterocyclic block copolymer grafted silica nanofillers for improving PEM properties

Surface functionalization of silica nanoparticles (SiNP) has gained attention as an efficient methodology in improving the properties of the proton exchange membrane (PEM). Here, we report the development of block copolymer grafted SiNP (BC-g-SiNP) as functional nanofiller which was further blended with oxypolybenzimidazole (OPBI) to prepare nanocomposite-based PEM. Block copolymer chains consisting of poly (N-Vinyl imidazole) (pNVI) and poly (N-Vinyl-1,2,4-triazole) (pNVT) were grown on the SiNP surface using grafting-from RAFT polymerization in one pot process. Two series of BC-g-SiNP namely pNVI-b-pNVT-g-SiNP and pNVT-b-pNVI-g-SiNP were synthesized by altering the polymer chain grafting sequence. A series of BC-g-SiNP was developed by varying chain length of each block to understand the effect of the chain sequence and length on the properties of nanofiller and their influence in altering the PEM properties. The block copolymer structure, chain sequence and chain length were confirmed by means of NMR and GPC analysis of the cleaved copolymer chains. The BC-g-SiNP exhibited core-shell morphology and thickness of the shell altered as the chain length and sequence of the grafted chains tuned. Phosphoric acid (PA) loaded OPBI/BC-g-SiNP nanocomposite PEM showed very high thermal, mechanical and chemical stabilities along with the proton conductivity as high as 0.278 S cm-1 at 180 °C in case of OPBI/P6(3%). A very clear-cut dependence of the PEM properties was observed on the architecture of the BC-g-SiNP such as chain length and sequence.

Highly selective custom‐made chitosan based membranes with reduced fuel permeability for direct methanol fuel cells

AbstractCustom‐made nanocomposite proton exchange membranes (PEMs) are fabricated using the blends of sulfonated chitosan (S‐Chitosan) and sulfonated graphene oxide (SGO) nanosheets for direct methanol fuel cells (DMFCs). Sulfonation of chitosan and GO are carried out by 1,3‐propane sultone and sulfanilic acid, respectively. Scanning electron microscope (SEM) with energy dispersive X‐ray investigation revealed that the thick, folded and wrinkled sheet‐like morphology of SGO and the existence of elemental sulfur. SEM and atomic force microscopy images showed the uniform dispersion of hydrophilic SGO nanosheets. Besides the S‐Chitosan/SGO membranes showed higher water uptake, swelling ratio and ion exchange capacity due to the enhancement in hydrophilicity. The modified PEMs displayed improvement in proton conductivity since the ion‐exchangeable sulfonic acid groups facilitate the proton conduction and effectively resist the methanol permeability by forming a strong hydrogen bond network with chitosan and thus diminish the void volume. Particularly, S‐Chiotsan‐1 membrane showed superior proton conductivity of 4.86 × 10−3 Scm−1 at (25°C), selectivity of 1.89 × 105 Scm−3 s and lesser methanol permeability of 2.57 × 10−8 cm2s−1. Overall results suggest that the S‐Chitosan/SGO membranes found to be a suitable alternate for Nafion® in DMFCs.

Fabrication of water-insoluble phosphotungstic acid-carbon nitride nanohybrids for promoting proton transport of nanocomposite proton exchange membranes

Incorporation of heteropolyacids (HPAs) could greatly improve proton conductivity of composite proton exchange membranes (PEMs). However, HPA leaching, due to their high solubility in water, remains one of the major problems hindering the further development of these composite PEMs. In this work, we have prepared water-insoluble P–C3N4 nanohybrids via the hydrothermal reactions between phosphotungstic acid (HPW) and graphitic carbon nitride (g-C3N4) nanosheets, in which HPW is chemically bonded with g-C3N4. The introduction of P–C3N4 nanohybrids promotes the proton transport by providing the strong acidity of HPW and the continuous 2D proton transport pathways, resulting in the proton conductivity reaching up to 0.086 S cm−1 in liquid water and 0.91 × 10−3 S cm−1 at 45% RH at 20 °C for the sulfonated poly(ether ether ketone) (SPEEK) nanocomposite membrane, which are 50% and 6000% higher than the SPEEK control membrane (0.056 S cm−1 and 1.5 × 10−5 S cm−1), respectively. The fuel cell performance for the MEA based on the SPEEK/P–C3N4 nanocomposite membrane is significantly improved, achieving a 38.1% increase in the peak power density at 80 °C under 92% RH. Therefore, our study demonstrates a facile and promising approach to prepare water-insoluble solid proton conductor with HPW components, which could be further applied to fabricate high performance nanocomposite PEMs.

Polysulfone and organo-modified graphene oxide for new hybrid proton exchange membranes: A green alternative for high-efficiency PEMFCs

Novel nanocomposite proton exchange membranes based on an organo-sulfonated derivative of the graphene oxide (SGO) incorporated in sulfonated Polysulfone (sPSU) were successfully fabricated via scalable, cost-effective and eco-friendly solution casting method for high-performing PEM fuel cells. The microstructure, physicochemical features and the electrochemical performance were widely investigated by a combination of various techniques including PFG-NMR spectroscopy, DMA and H2–O2 single-cell tests. Homogeneous and completely exfoliated sPSU-SGO nanocomposite membranes displayed outstanding thermal and mechanical stabilities as a result of strong interfacial interactions between the graphene nanoplatelets and the sulfonic acid groups on the polymer chains. This, together with the large number of acidic functionalities present in the SGO nanoadditive, greatly improved the water retention capacity of the membrane and increased proton transport through an effective Grotthuss-type mechanism, especially under very low humidification conditions. For instance, at 80 °C and 20% RH, the proton conductivity of the sPSU-SGO membrane was 9.4 mS cm−1 and H2/O2 cell test yielded a maximum power density of 182.6 mW cm−2 @ 110 °C and 25%RH. These values exceeded that of Nafion 212, used here as a benchmark, demonstrating that this hybrid electrolyte is an interesting and viable candidate for the next generation of high-temperature PEMFCs.

Two-dimensional metal-organic framework-graphene oxide hybrid nanocomposite proton exchange membranes with enhanced proton conduction

A novel two-dimensional (2D) zeolitic imidazolate framework-graphene oxide hybrid nanocomposite (ZIF-L@GO) is designed as an inorganic filler in sulfonated poly(ether ether ketone) (SPEEK). ZIF-L with unique leaf-like morphology is grown in-situ on the GO sheet in aqueous media at room temperature. The terminal imidazole linker in ZIF-L@GO and the –SO3H in SPEEK can form acid-base pairs in the membrane interface to produce low energy proton conduction highway. Benefiting from the unique structural advantage, the hybrid SP-ZIF-L@GO membranes displayed promoted physicochemical and electrochemical performances over the pure SPEEK. The SP-ZIF-L@GO-5 achieved a proton conductivity of 0.265 and 0.0364 S cm−1 at 70 °C-100% RH and 90 °C-40% RH, 1.76- and 6.24-fold higher than pure SPEEK, respectively. Meanwhile, a single cell based on SP-ZIF-L@GO-5 had an output power up to 652.82 mW cm−2 at 60 °C, 1.45 times higher than the pure SPEEK. In addition, the durability test was performed by holding open circuit voltage (OCV) for 24 h. The SP-ZIF-L@GO-5 provided better long-term stability than the pure SPEEK. These superior performance suggests a promising application in PEMFC.

Functionalized metallic transition metal dichalcogenide (TaS2) for nanocomposite membranes in direct methanol fuel cells

Novel nanocomposite proton-exchange membranes based on sulfonated poly(ether ether ketone) (SPEEK) and functionalized tantalum disulfide (S-TaS2) overcome the dichotomy of the properties of SPEEK membranes for direct methanol fuel cells.

Effect of sulfated metal oxides on the performance and stability of sulfonated poly (ether ether ketone) nanocomposite proton exchange membrane for fuel cell applications

In order to simultaneously improve the durability and performance of sulfonated poly (ether ether ketone) (SPEEK), series of hybrid membranes were prepared by doping an optimized amount of sulfated titania and sulfated zirconia-titania into the SPEEK matrix. The nanoparticles were synthesized using the sol-gel method and specified using XRD and EDS analysis. The solution casting method was used to prepare the membranes. Membrane characterization was performed through structural, morphological, thermochemical, and mechanical tests. The physicochemical characterization revealed that nanocomposite membranes are significantly improved compared with plain SPEEK. The single-cell performance test of nanocomposite based MEA record the power density peaks of 500mW cm−2 at 120°C and RH = 80%. Accordingly, sulfated metal oxide nanocomposite SPEEK-based membranes are promising alternative polymer electrolyte membranes for fuel cell applications.

Custom-made sulfonated poly (vinylidene fluoride-co-hexafluoropropylene) nanocomposite membranes for vanadium redox flow battery applications

Sulfonated poly (vinylidene fluoride-co-hexafluoropropylene) (SPVDF-co-HFP) based nanocomposite proton exchange membranes (PEM) are fabricated by simple solution casting method using polydopamine coated exfoliated molybdenum disulfide (PDA-MoS2) nanosheets as an alternative for Nafion® in vanadium redox flow batteries (VRFBs). PDA-MoS2 is synthesized by the etching of exfoliated MoS2 nanosheets with dopamine molecule by self-polymerization method. Various characteristic results clearly demonstrated that the incorporated PDA-MoS2 nanosheets homogeneously distributed into the SPVDF-co-HFP matrix and the presence of NH/NH2 group electrostatically interacts with SPVDF-co-HFP to form a strong acid-base pair and thus enhances the proton transport via Grotthuss type mechanism. Besides, the improvement in surface hydrophilicity provides the vehicle type conduction also. As a result, SPVDF-co-HFP/PM nanocomposite membranes showed higher proton conductivity in comparison with the pristine membrane. Especially SPVDF-co-HFP/PM-1 membrane demonstrated the excellent proton conductivity of 5.24 × 10−3 Scm−1 at 25 °C, lower vanadium-ion permeability of 1.05 × 10−8 cm2min−1 and highest membrane selectivity of 49.9 × 104 Scm−3min. On the other hand, vanadium-ion stability of the membrane increased by adding the PD-MoS2 content is attributed to their strong electrostatic attraction towards the polymer matrix. Overall results suggested that the SPVDF-co-HFP/PM-1 nanocomposite membrane is found to be a better alternative for commercially costly Nafion in VRFB applications.

Novel Nanocomposite PEM Membranes with Continuous Proton Transportation Channel and Reinforcing Network Formed by Electrospinning Solution Casting Method

AbstractIn this work, a kind of novel nanocomposite proton exchange membranes (PEMs) with excellent properties for fuel cell application is obtained through the combination of electrospinning and solution casting. PEMs are obtained via the electrospinning of solution of sulfonated poly(arylene ether ketone)s (SPAEK)s with carboxylic acid group (SPAEK‐COOH) inserted with nanocrystal cellulose (NCC) first, and then, the SPAEK‐COOH solution is cast on the obtained electrospinning membrane to fill the voids. According to the scanning electron microscopy image of the membrane surface and freeze‐fractured cross section, the nonporous membrane was successfully obtained. The water uptake and the swelling rate of the nanocomposite membrane with 2% NCC (NF‐NCC2) decrease to 62% and 61.5%, respectively, and the membrane shows much higher proton conductivity (0.29 S cm−1) than the pristine SPAEK‐COOH membrane (NF‐NCC0) (0.196 S cm−1) at 100 °C. Furthermore, NF‐NCC2 shows a tensile strength of 38 MPa, which is an increase of 36% compared to NF‐NCC0 (28 MPa). The orderly and uniform distribution of NCC in the electrospinning nanofiber and further in the membranes.

Immobilized phosphotungstic acid for the construction of proton exchange nanocomposite membranes with excellent stability and fuel cell performance

Phosphotungstic acid (HPW) has a good potential as nanofillers in nanocomposite proton exchange membrane with the prerequisite of solving the leakage issue. It is immobilized onto mesoporous graphitic carbon nitride (mg-C3N4) nanosheets surface, and then incorporated into sulfonated poly (aryl ether sulfone) (SPAES) membrane. Structures of the HPW/mg-C3N4 nanocomposites and corresponding SPAES/HPW/mg-C3N4 membranes are characterized by spectroscopic techniques. Fundamental properties and fuel cell performance of the fabricated nanocomposite membranes, and the leakage of HPW are investigated. Along with the highly suppressed HPW leakage, the SPAES/HPW/mg-C3N4 membranes show improved dimensional stability, water affinity and physicochemical stability, as well as better proton conductivity and fuel cell performance. At 80 °C and 60–100% RH, the SPAES/HPW/mg–C3N4–1.5 membrane exhibits 2–3.6 times peak power densities (354.9–584.2 mW/cm2) of the pristine SPAES membrane, and proton conductivity of 203 mS/cm, dimensional change less than 7.5% and weight loss of 1.4% in Fenton oxidation test at 80 °C.

New Approaches to the Preparation of Nanocomposite Proton Exchange Membranes for Fuel Cells

Experimental results on the development of two original approaches to obtaining new nanocomposite proton exchange membranes for low-temperature fuel cells are generalized. The first approach consists in in situ modification of the transport channels of commercial proton exchange membranes of the Nafion brand with interpenetrating polymer networks of the introduced polyelectrolyte based on cross-linked polystyrene sulfonate. The second approach is to create a proton exchange nanoscale phase based on polystyrene sulfonate in commercial hydrophobic polymer films. Polystyrene sulfonate is formed during thermal polymerization of styrene sorbed in the films without using ionizing radiation, followed by sulfonation. The influence of the conditions for obtaining membranes on the composition, morphology, transport properties, and results of testing the membranes in low-temperature fuel cells is considered.