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As technology advanced, new e-health solutions are evolved to empower people to manage their care at home. This study explored the needs for disease management in activity tracking using photo diary through older adults' subjective perspective. It further aimed to suggest which lifestyle measures, symptoms and behaviours would be meaningful to include in such a digital diseases care management program for technology design. Both photo diary and focus group discussion were used, 11 older adults with multiple metabolism-related chronic diseases (Mean age, 72.5 ± 6.14 years) were recruited and asked to carry out the photo diary to trace their living situation and needs using a tablet camera. A focus group discussion was applied to identify the needs of chronic disease management, based on the results of living context tracing. Five themes, regular physical activity, smart management of healthy behaviors, healthy diet, regular daily routine and social connection, were identified by content analysis from photo diary and the focus group discussion. The results indicated that the photo diary program can raise awareness and promotes positive behavior changes. It is believed that the E-approach can be applied to the effectively enhance older adults' self-management by monitoring their health status and their daily routine activities.

Interactions between silver nanoparticles and a cationic triblock copolymer significantly alter bulk material properties and can be tuned by functionalizing the polymer with different quaternary am...

Commercial proton exchange membrane heavy-duty fuel cell vehicles will require a five-fold increase in durability compared to current state-of-the art light-duty fuel cell vehicles. We describe a new composite membrane that incorporates silicotungstic heteroply acid (HPA), α-K8SiW11O40▪13H2O, a radical decomposition catalyst and when acid-exchanged can potentially conduct protons. The HPA was covalently bound to a terpolymer of tetrafluoroethylene, vinylidene fluoride, and sulfonyl fluoride containing monomer (1,1,2,2,3,3,4,4-octafluoro-4-((1,2,2-trifluorovinyl)oxy)butane-1-sulfonyl fluoride) by dehydrofluorination followed by addition of diethyl (4-hydroxyphenyl) phosphonate, giving a perfluorosulfonic acid-vinylidene fluoride-heteropoly acid (PFSA-VDF-HPA). A composite membrane was fabricated using a blend of the PFSA-VDF-HPA and the 800EW 3M perfluoro sulfonic acid polymer. The bottom liner-side of the membrane tended to have a higher proportion of HPA moieties compared to the air-side as gravity caused the higher mass density PFSA-VDF-HPA to settle. The composite membrane was shown to have less swelling, more hydrophobic properties, and higher crystallinity than the pure PFSA membrane. The proton conductivity of the membrane was 0.130 ± 0.03 S cm−1 at 80 °C and 95% RH. Impressively, when the membrane with HPA-rich side was facing the anode, the membrane survived more than 800 h under accelerated stress test conditions of open-circuit voltage, 90 °C and 30% RH.

Chemical degradation and mechanical degradation are the major challenges for heavy-duty vehicle fuel cell commercialization. Perfluorinated sulfonic acid is the benchmark material that has high proton conductivity and robust mechanical properties. However, chemical degradation can occur through radical formation during the fuel cell operation. Chemical degradation can also have a synergetic effect with mechanical degradation. Recent studies have used cerium and manganese additives to suppress the radical formation or chemical degradation caused by radicals. The limitation of the metal and metal oxide additives was the migration and agglomeration of the additives. Both migration and clustering can lead to changes in membrane morphology, resulting in a loss in proton conductivity. Our group has previously reported that immobilization of heteropoly acid to a fluoroelastomer can be used to both enhance proton conductivity and chemical degradation. The durability test has shown that the chemical durability was significantly enhanced, but the mechanical durability remained the challenge. In this study, we hypothesized that when a heteropoly acid can be chemically bound to the perfluorinated polymer and cast on a composite membrane with expanded polytetrafluoroethylene (e-PTFE) will enhance the chemical and mechanical durability without migration. Proton conductivity was measured using impedance spectroscopy. The structure-property relationship was studied using multi-scale morphology analysis methods such as scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), atomic force microscopy (AFM), and small-angle x-ray scattering (SAXS). The chemical degradation will be tested under the highly accelerated standard test (HAST) condition, a more severe fuel cell operation condition than the accelerated standard condition (AST). The mechanical durability of the composite membrane will also be tested on the HAST condition with humidity cycling.

There is still a need for membranes that operate in proton exchange membrane (PEM) fuel cells at hotter and drier conditions than can be achieved with current materials, >100°C and The key is to distribute the HPA on a perfluorinated polymer backbone in such a way that the natural tendency of the HPA to cluster and crystalize is suppressed. Using dehydroflourination chemistry we have learnt to functionalism PVDF type polymers with molecules that can act as anchor points for lacunary HPA, where a lacunary HPA has 1,2 or 3 tungsten oxygen clusters removed to give bonding points. After much research we now can produce these materials in large area thin film membranes. The base material outperforms the state of the art PEM under standard conditions and has the highest chemical stability of any PEM proposed to date. We are now varying the HPA structure to try and avoid the HPA clustering issue, these membranes are being sprayed on gas diffusion electrodes which act as the support to the tin films. This is allowing us to run these as fuel cells at higher temperatures to asses the potential of HPA functionalized membranes in these applications.

A polychloromethylstyrene-b-polypolycyclooctene-b-polychloromethylstyrene ABA triblock polymer was used as a backbone in a study to produce a chemically and mechanically robust anion exchange membrane (AEM). The material is easily scalable and the polypolycyclooctene segment (low Tm) makes the membrane flexible to handle. Comparison of the non-crosslinked triblock polymer functionalized with different cations namely; piperidinium, pyrrolidinium, tris(2,4,6-trimethoxyphenyl) phosphonium, and the benchmark trimethylammonium cation showed that the piperidinium functionalized membrane with an ionic exchange capacity of ca. 1.36 mmol.g− 1 had the highest OH− conductivity ca. 95 mS·cm− 1 at 80 °C, 95% RH, and the highest Cl− conductivity of ca. 31 mS·cm− 1 at 70 °C, 95% RH. The membrane with the piperidinium cation was the most chemically stable when immersed in 1 M KOH at 80 °C (with only 16% degradation after 14 days) compared to all the other cation functionalized membranes studied here. Photo-crosslinking with 1,10-decanedithiol (DT) eliminated the melting behavior of the polycyclooctene black and improved the mechanical stability of the films allowing

To further facilitate commercialization of automotive fuel cells, durability concerns need to be addressed. Currently the addition of a mechanical support in the membrane is able to adequately solve issues of mechanical degradation, but chemical degradation via oxygenated radical attack remains an unsolved challenge. Typical mitigation strategies use cerium or manganese species to serve as radical scavengers, but these ions are able to migrate in the membrane and even leach out of the system. The approach used in this study is to covalently link and immobilize a heteropoly acid (HPA), more specifically 11-silicotungstic acid (HSiW11), a lacunary HPA of the Keggin structure to a fluoroelastomer, serving as both a radical decomposition catalyst and the proton conducting acid. This dual functionality allows for both high content of radical scavenging species and high ion-exchange capacity. An efficient three step, high yield (77%), commercially viable synthesis for this polymer is reported. The synthesis route for making this new heteropoly acid functionalized polymer is confirmed using infrared spectroscopy (IR), nuclear magnetic resonance (NMR) spectroscopy, and thermogravimetric analysis (TGA). The material exhibits clustering of the HSiW11 moieties, resulting in a poorly connected proton conducting phase when dry, but excellent conductivity is achieved at elevated humidities (0.298 S cm−1 at 80 °C and 95% RH). The proton conductivity shows an enhancement above 60 °C due to a softening of the polymer, as shown by DSC. Under an aggressive chemical accelerated stress test (AST), 90 °C, 30% RH, zero current, and pure O2, the PolyHPA losses only 0.05 V of open circuit voltage (OCV) after 500 h, greatly out performing any other material reported in the literature. For comparison, the Nafion® N211 fuel cell drops below 0.8 V after only 76 h under the same conditions. In fuel cell testing the PolyHPAs have outstanding chemical stability and also possess very low in situ high frequency resistance (HFR) leading to high performance (1.14 W cm−2 at 2 A cm−2), compared to 1.11 W cm−2 for the Nafion® N211 fuel cell at the same current. At 75 wt% HSiW11 loading, the fuel cell HFR showed a 22% decrease over N211.

Anion exchange membranes (AEMs) have recently attracted interest for applications in fuel cells, electrolyzers, redox flow batteries, reverse electrodialysis, and water purification. In contrast to proton exchange membranes (PEMs), AEMs operate in base instead of acid and facilitate the transport of anionic species. In fuel cells and electrolyzers, this allows for more facile kinetics of the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) respectively. Therefore, AEM-based devices provide the opportunity to utilize non-precious metal catalysts to achieve similar performance to Pt-based catalysts and a substantially reduced cost. The electrodes of these devices are comprised of a heterogeneous mixture of conductive carbon support, catalyst particles, and ionomer, which form a triple-phase boundary where the electrochemical reactions take place. The ionomer is an alkaline polymer electrolyte similar to the AEM which transports OH- and water to/from the catalyst surface and promotes reactant transport. The electrode layers in PEM-based fuel cells were developed empirically, and it was not until recently that research efforts were dedicated to investigating the heterogeneous microstructure and triple-phase boundary that form. Currently, the catalyst layer as it exists in an operating device is not well understood due to its complex nature; however, model interfaces between ionomers and catalyst particles have been used to provide valuable insight on ionomer-catalyst interfacial interactions. It is known from studies with Nafion® that restructuring of the polymer morphology can occur when it exists as an ionomer thin film at a catalyst interface. The behavior of the thin film ionomer changes compared to its bulk characteristics, which ultimately affects electrode kinetics by altering the nature of its microstructure, leading to shifts in morphology, water uptake properties, and ionic and water transport networks. Initial work was driven by the overarching hypothesis that the polymer-catalyst interfacial interactions could be modified by changing the ionomer chemistry. This was investigated by studying interactions between silver nanoparticles and anion exchange ionomers functionalized with two different quaternary ammonium cations, using our previously reported block copolymer backbone polychloromethylstyrene-b-polycyclooctene-b-polychloromethylstyrene (PCMS-b-PCOE-b-PCMS) functionalized with either trimethylammonium (TMA) or methylpiperidinium (MPRD) quaternary ammonium cations. Our early findings indicated there were interactions between silver nanoparticles and C=C groups in the polycyclooctene midblock of the polymer backbone. This motivated the development of a modified anion exchange polymer by hydrogenating the PCOE midblock in PCMS-b-PCOE-b-PCMS to synthesize a polyethylene (PE) midblock. Hydrogenation was achieved through a reaction with p-toluenesulfonyl hydrazide. The improved characteristics of the PE-based membrane have prompted studies investigating the comparison of saturated and unsaturated ionomers. A uniquely tunable polymer system was developed which has enabled further investigations of ionomer thin films on silver substrates. The thin film geometry allows for the use of grazing incidence small angle x-ray scattering (GISAXS) and atomic force microscopy (AFM) to study the interfacial morphology as a function of ionomer chemistry. Restructuring of the polymer morphology compared to its bulk properties has been confirmed, and our initial findings on the contribution of different cationic moieties will be discussed in the results of this report.

The heterogeneous microstructure of the electrode in polymer electrolyte-based electrochemical devices features a complex mixture of interacting species, including ionomer, catalyst particles, and typically a conductive carbon support. The triple-phase boundary which forms between these three components significantly impacts the transport of water, ions, and reactant and product species to and from reaction sites. Hence, overall performance of the electrochemical device is significantly impacted by the structures that form in the electrode, which are driven by interactions between the ionomer and catalyst components. It is known that interactions at the ionomer-catalyst interface can facilitate restructuring of the ionomer morphology, ultimately affecting transport networks. Therefore, a more fundamental understanding of ionomer-catalyst interactions can aid in the development of ionomer chemistries that result in desirable interfacial morphologies and electrode structures. Since alkaline systems can leverage the ORR capabilities of non-noble metal catalysts beyond Pt, this work focuses on interactions with silver, which has been shown to have ORR activity akin to Pt catalysts. Our previous work has shown that the quaternary ammonium cations trimethylammonium (TMA) and methylpiperidinium (MPRD) both interact with silver and can affect bulk properties of the ionomer, including crystallinity and water uptake. To continue this study, a set of tunable block copolymers, post-functionalized with either TMA or MPRD, are used to investigate how cation chemistry influences the resulting interfacial morphology of the ionomer. Model interfaces between ionomer thin films and silver surfaces are fabricated and studied using a combination of environmental GISAXS and AFM to assess morphological characteristics such as domain size and orientation under relevant electrochemical device conditions. These efforts will lead to a better understanding of the ionomer-catalyst interface and will provide key insight toward rationally designing block copolymers for the alkaline electrochemical devices.

Proton exchange membranes (PEMs) are considered as the most promising material for fuel cell automobile applications due to their high proton conductivity and power density. The radical attacks with peroxide formation cause lower durability, which is a major challenge to further commercialize fuel cell vehicles. Cerium and manganese cations and oxides have been implemented as radical scavenging agents to overcome the challenge from radical attacks. However, the additives tend to not stay on the initial location but move during the operation due to migration and diffusion. The migration results in cluster formation and eventually the additives may dissolve and leave the membrane system. Our previous work modifying commercial fluroelastomers with chemically bonded polyoxometalate resulted in a membrane with radical scavenging properties while inhibiting additive clustering. Advancement in PEM durability with additives has implications not only for the light-duty fuel cell vehicles but also for medium and heavy-duty vehicles applications, which would aid the widespread of commercialization of fuel cell vehicles. This work focuses on characterizing the blended perfluorinated sulfonic acid (PFSA) ionomer membrane with the chemically bound radical scavenger to enhance the durability of the membrane. Proton conductivity of the membrane was characterized under controlled relative humidity and temperature with electrochemical impedance spectroscopy (EIS). Ionic Exchange capacity of two or more proton conductive sites was measured using titration method. Correlation between water uptake and membrane properties is discussed and measuring using dynamic vapor sorption (DVS). Thermal stability was investigated through thermalgravimetric analysis (TGA).

In acidic fuel cells, the ionomer and catalyst layer were developed empirically, and only recently studies have begun investigating the success of the heterogeneous microstructure and triple-phase boundary. Currently, the catalyst layer is not well understood due to its complexity; however, model interfaces between ionomers and catalyst particles have been used to provide valuable insight on ionomer-catalyst interfacial interactions. It is known from studies with Nafion® that restructuring of the polymer morphology can occur when it exists as an ionomer thin film at a catalyst interface. The behavior of the thin film ionomer changes compared to its bulk characteristics, which ultimately affects electrode kinetics by altering ionic and water transport networks. In the field of alkaline fuel cells, there is limited research published on ionomer developments in general or on specific interactions between ionomers and catalysts. The few fuel cell studies that compare the effects of ionomer chemistry have conflicting conclusions, which likely arise because the ionomer chemistries interact with Pt in different ways. Overall, this provides the motivation for our work to study idealized structures in the electrode, specifically to elucidate and modify interactions occurring at the interface between ionomers and non-PGM catalysts. This insight will enable the rational and systematic development of ionomer chemistry with the ultimate goal of improving electrode kinetics for a variety of important electrochemical reactions. We have synthesized a large number of model cationic block co-polymers, diblocks, triblocks and pentablocks (AB, ABA, ABABA). Where the hydrophobic block is either polyisoprene or polycyclooctadiene, or their hydrogenated analogues, polymethylbutylene or polyethylene. The other block is polychloromethylstyrene that can be quaternized with a variety of amines to vary the interaction with the surface, inmost of work we use the relatively simple benzyltrimethylammonium (TMA) cation or the reportedly more stable and more bulky benzylmethylpyrolidinium (MPRD) cation. Our initial studies using commercial Ag nano powders showed that the olefinic groups of the polymers interacted wit the Ag and that the interaction of the cations with the Ag surface could completely remove the crystallinity from the entire sample in the case of the polyethylene block. Probing the effects of these interactions on electrocatalysis of the oxen reduction reaction is on going and we will report our progress in this paper. To further constrain the polymers we have also studied them as thin films on flat Si wafers and the same substrate coated with thin metallic films and studied by GISAXS. When block co-polymers are spin coated on plain silicon wafers we almost always see no scattering as there is no alignment of the polymer on the silicon surface. When a thin layer of silver is coated onto the silicon, discrete alignment of features perpendicular to the surface are observed for many of the polymers we have synthesized on the nanoscale. The size of these features in the thin films is not always correlated with the block sizes observed in the bulk films by SAXS. AFM imaging of the polymer air interface suggests that these vertically aligned features persist throughout the film, a property presumably needed for transport, but that the size can vary. The data shown below is typical of aligned vertical triblock ABA polymers on Ag. We have also investigated these thin films as a function of temperature and hummidity and observed transients of the changes in the morphology of these materials. In this paper we will show how these interactions can be utilized for the beneficial development of electrocatalysts. Figure 1

Ion exchange membranes are commonly used in many applications such as water desalination and wastewater nutrient recovery. The permselectivity of ion exchange membranes is one of its most critical properties, but often must be balanced with adequate permeability. High permeation of negative ions coupled with low permeation of positive ions is desirable in anion exchange membranes (AEMs). However, separation of these oppositely charged ions tends to suffer as the concentration of the feed solution increases, thereby limiting the range of processable feed solutions. In this work, a robust AEM was synthesized with a polychlorostyrene-b-polycyclooctene-b-polychlorostyrene ABA triblock polymer quaternized with methylpiperidine. By adjusting the block length of polychlorostyrene, different sized water channels are formed within the AEM which result in highly tunable anion selectivity. Small angle x-ray scattering (SAXS) and TEM confirm the size of these water channels while permeability and sorption tests elucidate the influence of these different morphologies on separation ability. The AEM also has low water uptake for increased stability and mechanical strength, which is vital in terms of extending the membrane lifetime. With this robust material, AEMs may enable the desalination of highly saline waters such as seawater and enable more economic wastewater nutrient recovery.

Redox flow batteries (RFBs) remain one of the most promising technologies that are actively explored for grid-scale energy storage from discontinuous power sources such as wind and solar.[1] Proliferation of RFB technology has resulted in a need for continued development and understanding of new redox couples and improved separator membranes for RFB operation, while reducing cost. Membranes employed in RFB technology are largely comprised of the perfluorosulfonic acid (PFSA) family (e.g. Nafion, Aquivion, and 3M PFSA) which own their functionality to the phase separated structure composed of ionically conductive hydrophilic domains distributed within an inert and mechanically stable hydrophobic matrix.[2] PFSA membranes are also susceptible to high crossover of redox active species, leading to parasitic losses in capacity that can only be solved by the development of highly selective separator membranes. In this work, we report our progress in developing membranes that exhibit high selectivity by employing heteropoly acid (HPA) ion conductors that have been covalently tethered to the backbone of a polymer support. HPA-loaded membranes are promising due to the highly mobile protons associated with the HPA molecule[3] alongside the hydrophobic polymer that provides mechanical strength that is capable of preventing crossover. PFSA membranes were used as a baseline to access the quality of the newly developed HPA-loaded membranes by measuring the selectivity which involves measurement of the membrane conductivity and permeability. The HPA-loading was varied on a mass base in order to evaluate the trade-offs between increased membrane conductivity, which tends to occur with increased permeability of redox active species. Selected membranes were subjected to cell testing in a RFB based on the iron-hydrogen to gauge cell performance. References: Perry, M.L. and A.Z. Weber, Advanced Redox-Flow Batteries: A Perspective. Journal of the Electrochemical Society, 2016. 163(1): p. A5064-A5067. Kusoglu, A. and A.Z. Weber, New Insights into Perfluorinated Sulfonic-Acid Ionomers. Chemical Reviews, 2017. 117(3): p. 987-1104. Motz, A.R., et al., Heteropoly acid functionalized fluoroelastomer with outstanding chemical durability and performance for vehicular fuel cells. Energy & Environmental Science, 2018. 11(6): p. 1499-1509. Acknowledgements: This study was funded with support of the U.S. Department of Energy under contract number DE-AC02-05CH11231 as sub-contract under Colorado School of Mines and United Technologies Research Center.

The heterogeneous microstructure of the electrode in polymer electrolyte-based electrochemical devices is not well understood. Due to its complex nature, it is challenging to investigate in a meaningful way. Model systems need to be designed to study controlled interfaces between polymer electrolytes and catalyst particles or surfaces. It is known from studies on proton exchange membranes that restructuring can occur at the polymer-catalyst interface and propagate into the bulk morphology of the material. This is potentially to the detriment of reactant and product species transport in the electrode, and ultimately affects device performance. There is currently little to no work reported on interactions between anion exchange polymers and non-precious metal catalysts more relevant to alkaline systems, such as silver or nickel. This research utilizes a highly tunable ABA triblock copolymer (polychloromethylstyrene-b-polycyclooctene-b-polychloromethylstyrene) to investigate different parameters within the chemistry space and how they influence interactions between the polymer and a catalyst surface. The synthesis route for the triblock copolymer has been optimized to achieve a variety of block lengths and A:B ratios, which ultimately lead to a range of characteristics (ionic conductivity, water uptake, mechanical properties) and morphologies when they are post-quaternized to produce AEMs. Additionally, the polycyclooctene (PCOE) midblock contains C=C double bonds that allow for a variety of post-modifications, such as radical crosslinking and hydrogenation. This system has given us a way to make changes to the chemistry and morphology of the polymer and investigate the effect on interactions at a silver surface. The polymer-catalyst interface has been fabricated for study in two different model systems – as a thin film on a flat surface of silver and in a constrained environment of silver nanoparticles. The structure and properties of the anion exchange polymer in these systems will be representative of any changes that occur due to interactions with the catalyst. In the thin film geometry, the properties of the polymer are studied by comparing the ‘bulk’ properties (represented as a thin film on atomically flat silicon where there are no interactions) with those of a thin film on a silver surface. Samples of varying thickness and chemistry have been prepared and the morphology of each system has been investigated using grazing incidence small angle and wide angle x-ray scattering (GISWAXS) and atomic force microscopy (AFM). Clear differences were found between the bulk properties and those at the silver interface that indicate a strong interaction between the anion exchange polymer and a silver catalyst surface. These change as a function of the various parameters under investigation, including A:B block ratios, molecular weight, chemistry of the polymer backbone, and chemistry of the quaternary ammonia cation group. For AEMs in silver nanoparticle constrained environments, properties under investigation are compared to those of the bulk polymer. Areas of current work include studying changes in thermal characteristics (using thermogravimetric analysis and differential scanning calorimetry), morphology (using transmission electron spectroscopy and small angle x-ray scattering), backbone crystallinity (using wide angle x-ray scattering), ionic and electrical conductivity, alkaline stability, vapor and liquid water uptake, and mechanical properties. Interactions between specific chemical groups are also being investigated with Fourier-transform infrared spectroscopy (FTIR). Furthering the understanding of interactions and morphological changes at the polymer-catalyst interfaces will provide a framework for rational design of anion exchange polymers. Ultimately, improvements in polymer design can have significant impacts on the transport of species in the electrode layer and overall device performance.

Heteropoly acids (HPAs), a subclass of the polyoxometalates, are a class of proton conducting radical activating or decomposing molecules. Several types of HPAs have demonstrated the ability to improve membrane chemical stability and proton conductivity through polymer blends, but they still suffer from migration of the HPA species and only result in marginal gains. A method of covalent bonding HPAs to carbon in the catalyst layer has also shown some improvements in chemical stability, but chemical degradation mitigation within the membrane is needed. Our group has developed two membrane platforms with HPAs covalently attached and immobilized within a polymer membrane, serving as the proton conducting acid. More recently, the outstanding chemical stability of one of these platforms has been demonstrated, however, the stability demonstrated in this study was criticized for using rather thick, 80 µm membranes in sub-scale fuel cells. In a recent study a 50 cm2 fuel cell was fabricated using a thin, 25 µm membrane with covalently attached silicotungstic acid, which was subjected to an accelerated stress test for chemical degradation and displayed an OCV decay rate of 520 µV h-1. To the authors knowledge, this is the first reported fuel cell of a larger practical area containing a hybrid HPA film and represents a significant step towards demonstrating this technology on a commercially relevant scale. The resulting data was analyzed to show the loss in OCV is mainly due to an electrical short and not increased reactant gas crossover. This study further analyzes the chemical stability observed in these membranes and proposes a mechanism for radical decomposition. A reaction mechanism is proposed utilizing reactions found in literature as well as density functional theory (DFT) calculations. The main conclusion from this work is that covalently attached HPAs could be more efficient radical scavengers with less susceptibility to migration, accumulation, and leaching when compared to the use of Ce(III) cations. We have recently realized a method for cleaning these membrane materials, removing many of the impurities formed during synthesis and have also begun to cross-link these material to eliminate swelling and achieve a dimensionally stable films. These much-improved materials show even higher performance in fuel cells and could potentially solve many of the issues associated with the PFSA materials. In addition the HPA functionalized films have advantages in selective low area spec resistant membranes for redox flow batteries with a variety of redox couples. We all shoe that these membranes can facilitate redox flow batteries with labile vanadium substituted HPAs.

Studies of proton transport in novel materials are important to enable a large array of electrochemical devices. In this study, we show that heteropoly acids (HPAs) when immobilized in polymer matrixes have highly mobile protons. Divinyl-11-silicotungstic acid, an HPA, was copolymerized with butyl acrylate and hexanediol diacrylate at various weight percentage loadings from 25% to 85% using UV initiated polymerizations. The resultant films were tan colored flexible sheets of ca. 120 μm thickness. The morphology of these films varied with loading, showing phase separation into clustered HPA above a 50 wt % loading and lamella morphologies above an 80 wt % loading. Water uptake was strongly associated with the HPA clusters, which facilitated transport of protons. This was realized by proton conductivities as high as 0.4 S cm–1 at 95 °C and 95% RH and 0.1 S cm–1 at 85 °C and 50% RH. Pulse field gradient spin echo NMR measurements indicated that water self-diffusion was fast (1.4 × 10–5 and 4.4 × 10–5 cm2 s–1...

Aim The rapid growth of the elderly population has given rise to the need for better geriatric care. The present study explored the common conditions of elderly outpatients with multiple physician visits in order to develop feasible clinical indicators that can be rapidly administered for the evaluation of geriatric syndromes in outpatient settings. Methods The National Health Insurance Research Database (2008) was analyzed. Claims for elderly outpatients with more than two physician visits in the same day were retrieved. The primary diagnoses, types of prescriptions and comorbidities were cross-examined. Results The overall prevalence rate for elderly patients with multiple physician visits ranged from 28.41% to 39.40%, and which increased steadily with age. A maximum of seven physician visits in a single day was observed. The most common multiple physician visit was two visits per day, with a prevalence rate of 30.97%. The two most common accompanying conditions were hypertension (3.79%) and type 2 diabetes mellitus (3.68%). There was a greater relative increase in the prevalence of senile dementia and chronic obstructive pulmonary disease in older age groups. The three overall leading specialties were cardiology, internal medicine, and ophthalmology; however, rehabilitation medicine was the most common female-specific specialty. The most commonly prescribed medications were antihypertension drugs. The most prevalent comorbidity was type 2 diabetes mellitus and hypertension. Conclusion We conclude that our data represent crucial information for the design of concise assessment metrics for application to the most chronic conditions in an effort to implement better geriatric healthcare. Geriatr Gerontol Int 2014; 14: 372–380.

Copolymers of vinyl phosphonic acid with zirconium vinyl phosphonate have been synthesized via free radical polymerization from immiscible mixtures into amorphous, transparent, water stable, flexible membranes. Ion exchange capacities range from 6 to 10 meq/g corresponding to equivalent weights well below 200 g/mol. A 20wt% loading of the vinyl zirconium phosphonate co-monomer is XRD amorphous. It is shown that 1.5 of the 2 protons in the beginning acidic groups are dissociated in the 20wt% VZP loaded ionomer allowing these materials to have high proton conductivities, up to and exceeding 0.1 S cm-1 at 80{degree sign}C and 80%RH. Water uptake measurements show very little swelling of the material below 70%RH and ca. 1 water per proton at low RH. Proton conductivity under dry conditions, roughly 0.05 S cm-1 with a lambda < 1, indicates that the material conducts protons under limiting hydration conditions and strongly implicates transport by a pure Grotthuss mechanism.

Background: Faster than anticipated increases in population, aging is making the issue of frailty among the elderly increasingly important. Despite general agreement that a frailty assessment is important for planning care for the older adults, a lack of consensus remains regarding the best methodology to use for frailty assessments.Purpose: The aim of this study was first to cross-examine results between perception of frailty and physical assessment outcomes then try to establish frailty indicators for elderly people in Taiwan.Methods: This study used both qualitative and quantitative methods. From August to September 2010, researchers recruited a convenience sample of 10 community older adults from six different elderly centers in northern Taiwan. Qualitative in-depth interviews were conducted in Mandarin or Taiwanese and audiotaped. After the in-depth interview, researchers conducted a series of physical assessments on the participants.Results: Ten elderly women were interviewed and assessed. The three themes identified by this study related to frailty perception included overall physical function performance, psychological health, and physiological health. These reflected the concept of successful aging. Participant frailty was compared with subjective perceptions to identify and/or check for consistency between qualitative and quantitative results. Although quantitative results revealed that participants were in fairly good health, there were many complaints about frailty during the qualitative interview. Better sensitive measures reflecting frailty changes are thus needed.Conclusions: These indicators can be considered as an integration of all maintained functions. We hope that results will provide better insights into understanding the process of frailty among the older adults.

We have fabricated proton conducting films using monomers based on vinyl substituted silicotungstic acid heteropoly acids (HPAs) and acrylate co-monomers. In this work we probe the morphology of this system based on increasing the weight loading of the HPA to 85 wt%. Although impressive proton conductivities can be achieved with these films under hotter and drier operating conditions than in conventional proton exchange membranes, the materials have mechanical limitations. We have begun to develop more practical systems in which ester and methylene groups are eliminated from the polymer backbone.

Anion exchange membrane (AEM) fuel cells offer a promising alternative to proton exchange membrane fuel cells. AEMs utilize more facile electrochemical reaction kinetics by operating in a basic environment, which should theoretically allow them to utilize non-precious metal catalysts such as silver or nickel. This research focuses on the characterization of a novel block copolymer AEM and elucidating the anion exchange polymer-catalyst interface. The block copolymer system has been engineered to combine the features of high ion conductivity of a hydrophilic block with the reinforcing properties of a hydrophobic block. The ABA triblock polymer utilizes a polychloromethylstyrene-b-polypolycyclooctene-b-polychloromethylstyrene (PCMS-PCOE-PCMS) backbone and dimethylpiperidinium (MPRD) cation, which has shown excellent hydroxide stability. This work aims to first understand the bulk properties of the polymer and then subsequently compare them to the properties of the material at the catalyst interface, where potential interactions could lead to restructuring of the polymer and thus alter the transport of water, hydroxide, fuel, and electrical conduction. This will be studied by fabricating well-defined interfaces between the polyelectrolytes and catalyst surface, either as thin films on an electroactive surface of silver (Ag) or in a constrained environment of Ag colloids. If the volume fraction of Ag colloids is small, the polymer properties will be representative of those at the polymer-catalyst interface. In-plane conductivity will be measured by EIS using a four fine Pt wire electrode fixture, from which an activation energy of aqueous ionic movement can also be derived. To further understand how the mechanical properties of the polymer are affected at the catalyst interface, dynamic vapor sorption will be used assess water content as a function of relative humidity (RH) and thermogravimetric analysis will be used to determine thermal properties. Additionally, morphological changes and restructuring at the catalyst interface as a function of RH will be elucidated using AFM and GISAXS. The information obtained from these techniques will determine whether the polymer is aligned with the catalyst surface. Pulse field gradient spin echo (PFGSE) NMR spectroscopy will be used to study the movement of water molecules (1H NMR), carbonate and bicarbonate (13C NMR), and fluoride (19F NMR). When performed at varying temperature and RH, self-diffusion coefficients can be obtained, and the tortuosity of the transport pathway can be estimated. ATR FTIR spectroscopy will also be used to investigate the nature of the water content and compare it between the bulk polymer and polymer-catalyst interface. Cyclic voltammetry using a bipolar membrane fuel cell will also be used to study the adsorption and desorption on the catalyst layer. The characterization of the polymer-catalyst interface and further understanding of any restructuring that occurs will provide a knowledge base for optimizing the design of an AEM.

Many electrochemical processes for energy conversion are more facile in base than in acid. But, there are no good commercial anion exchange membranes (AEM), that are chemically stable, have dimensional stability in water, and still have high ion conductivities resulting in reasonable area specific resistances as thin films. In collaboration with the University of Massachusetts, Amherst we have developed an innovative polymer system that can be tuned for almost any application needing an AEM in electrochemical engineering. The material is a symmetrical ABA triblock polymer with a facile synthesis amenable to large-scale production. The A blocks are the ridged ion conducting hydrophilic blocks and are derived from polymethylchlorostyrene (PCMS) and functionalized with next generation C6 ring cations that give the polymers some of the highest know chemical stability so far observed. Here we functionalize the materials via quaternization of the PCMS with methylpyrrolidinium (MPRD) cations. We can process the A block to control swelling. In addition we can easily achieve ion exchange capacities >2.0meq g-1 which leads to phase separated materials with ionic conductivities > 0.1 S cm-1. The material phase separates into a short range lamella morphology as confirmed by TEM and SAXS. The B block is based on cycloctene or cycloctadiene and is designed to be very soft, so soft in fact that it melts at 50°C. The mechanical properties of the B block are then easily tuned by careful control of a photocrosslinking chemistry involving a dithiol. Through control of the A and B block lengths and the cross-linking steps we can achieve AEMs that can be as little as 10 μm in thickness with some of the highest ionic conductivity, chemical stability, control of swelling, and device ready mechanical properties. Because the material is solvent castable it also makes an excellent starting point to develop ionomers for the electrodes in fuel cells and other devices. We are supplying the material to ProtonOnSite for testing in electrolysis devices, the Army Research Laboratory for testing in fuel cells and JCESR for testing in redox flow batteries, and we will present the results of these studies and discuss the path forward to making our material device ready.

In this study, polarization and impedance experiments were performed on a direct dimethyl ether fuel cell (DMEFC). The experimental setup allowed for independent control of water and DME flow rates. The DME flow rate, backpressure, and water flow rate were optimized. Three heteropolyacids, phosphomolybdic acid, H3PMo12O40. (HPMo), phosphotungstic acid, H3PW12O40, (HPW), and silicotungstic acid, H4SiW12O40, (HSiW) were incorporated into the anode catalyst layer in combination with Pt/C. Both HPW-Pt and HSiW-Pt showed higher overall performance than the Pt control. Anodic polarizations were also performed, at 30 psig, Tafel slopes of 67 mV dec−1, 72 mV dec−1, and 79 mV dec−1 were found for HPW-Pt, HSiW-Pt and the Pt control, respectively. At 0 psig, the Tafel slopes were 56 mV dec−1, 58 mV dec−1, and 65 mV dec−1 for HPW-Pt, HSiW-Pt and the Pt control. The trends in the Tafel slope values are in agreement with the polarization data and the electrochemical impedance spectroscopy results. The addition of phosphotungstic acid more than doubled the power density of the fuel cell, compared to the Pt control. When the maximum power density obtained using the HPW-Pt MEA is normalized by the mass of Pt used, the optimal result, 78 mW mg−1 Pt, the highest observed at 30 psig and 100 °C to date.

We have fabricated proton conducting films using monomers based on vinyl substituted silicotungstic acid heteropoly acids (HPAs) and acrylate co-monomers. In this work we probe the limits of this system based on increasing the weight loading of the HPA to 85 wt%. Although impressive proton conductivities can be achieved with these films under hotter and drier operating conditions than in conventional proton exchange membranes, the materials have mechanical limitations. We show that very different film morphologies can be prepared based on whether or not the film is polymerized thermally or by UV light. In general the UV cured films have superior proton conductivity, but have a linear morphology resulting in a brittle film. The thermally cured films have a clustered morphology with good mechanical attributes but have poor proton conductivity.

Highly conducive to high conductivity: Polyoxometalates were incorporated in the backbone of a hydrocarbon polymer to produce proton-conducting films. These first-generation materials contain large, dispersed clusters of polyoxometalates. Although the morphology of these films is not yet optimal, they already demonstrate practical proton conductivities and proton diffusion within the clusters appears to be very high.

A total of 18 heteropolyacids (HPAs) were investigated to determine their activity as non-Pt oxygen reduction reaction (ORR) catalysts in polymer electrolyte membrane fuel cell cathodes (PEMFCs). Polarization curves, cyclic voltammetry and impedance spectroscopy determined that, of the HPAs tested, only molybdenum based HPAs are active for the ORR and that vanadium substitutions improved the activity. The reduction potentials of the HPAs in the fuel cell environment were determined by cyclic voltammetry. This showed that no activity is seen above 0.55 V, as the catalysts must first be reduced in situ by 4e − before the HPA can reduce oxygen. The potential at which the HPA can be reduced has been determined to be the limiting factor when using these catalysts for ORR in PEMFCs. Power densities of 67 mW/cm 2 at 0.2 V were obtained using H 5 PMo 10 V 2 O 40 . Molybdenum based HPAs were covalently bonded to the carbon achieving mass loadings ∼3× that obtained through adsorption. Using this approach catalyst, performance was improved to 86 mW/cm 2 at 0.2 V. The increased loadings did not significantly increase the potentials at which the HPA becomes active for the ORR. We were able to show that MEA degradation, as measured by F − emission rates, using these catalysts are reduced during accelerated testing protocols.

The heteropoly acids (HPAs) are a class of inorganic oxides that have some of the highest solid state proton conductivities known at room temperature. At elevated temperatures proton diffusion coefficients in these crystalline materials increase, but, not all the protons are mobile resulting in a decrease of the observed proton conductivity. The proton conductivity in these materials is heavily dependant on the hydration state of the HPA. In order to develop new PEMs based on the HPAs for elevated temperature, dry operation, it will be necessary to both immobilize the HPA and ensure that all of the protons are mobile all of the time. If both these objectives can be obtained a new class of PEMs will be developed that could facilitate the use of PEM fuel cells in automotive applications. We have created a new class of PEM by polymerizing HPA monomers with appropriate co-monomers to produce films with unique proton conducting properties.

In this work, polarization and electrochemical impedance spectroscopy experiments were performed on a direct methanol fuel cell (DMFC). Two heteropoly acids, phosphomolybdic acid (PMA) and phosphotungstic acid (PTA), were incorporated into the anode catalyst layer in combination with Pt/C. Both PTA-Pt and PMA-Pt showed higher performance than the Pt control at 30 psig of backpressure. Anodic polarizations were also performed, and Tafel slopes were extracted from the data. An equivalent circuit model which incorporated constant phase elements (CPEs) was used to model the impedance data. From the impedance model it was found that the incorporation of HPAs into the catalyst layer resulted in a reduction in the resistance to charge transfer, Rct. This shows that these two heteropoly acids do act as co-catalysts with platinum for methanol electrooxidation. However, the performance seen here is below that of PtRu catalysts.

Heteropoly acids were investigated to determine their activity as non-Pt oxygen reduction reaction (ORR) catalysts in polymer electrolyte membrane fuel cell cathodes (PEMFCs). Polarization curves, cyclic voltammetry, and impedance spectroscopy results determined that, of the HPAs tested, only Mo based HPAs are active for the ORR and that V substitutions can improve the activity. Power densities of 67mW at 0.2V were obtained using H5PMo10V2O40. The catalysts must first be reduced insitu before the HPA can reduce oxygen. The reduction potentials of the HPAs in the fuel cell environment were determined by cyclic voltammetry and provide an explanation for why no activity is seen above 0.55V. Impedance spectroscopy confirmed that V substitutions increase catalytic activity. The potential at which the HPA can be reduced by 4 electrons has been determined to be the limiting factor when using these catalysts for ORR in PEMFCs.

Polarization and electrochemical impedance spectroscopy experiments were performed on a direct methanol fuel cell (DMFC) incorporating the heteropoly acids (HPAs) phosphomolybdic acid, H 3 PMo 12 O 40 , (HPMo) or phosphotungstic acid, H 3 PW 12 O 40 , (HPW) in the anode Pt/C catalyst layer. Both HPW-Pt and HPMo-Pt showed higher performance than the Pt control at 30 psig of backpressure and at ambient pressure. Anodic polarizations were also performed, and Tafel slopes were extracted from the data between 0.25 V and 0.5 V. At 30 psig, Tafel slopes of 133 mV/dec, 146 mV/dec, and 161 mV/dec were found for HPW-Pt, HPMo-Pt and the Pt control, respectively. At 0 psig, the Tafel slopes were 172 mV/dec, 178 mV/dec, and 188 mV/dec for HPW-Pt, HPMo-Pt and the Pt control. An equivalent circuit model, which incorporated constant phase elements (CPEs), was used to model the impedance data. From the impedance model it was found that the incorporation of HPAs into the catalyst layer resulted in a reduction in the resistances to charge transfer. This shows that these two heteropoly acids do act as co-catalysts with platinum for methanol electrooxidation.

We have successfully immobilized several HPA on carbons using covalent attachment. The morphology of these materials is still under investigation, but the hybrid HPA carbons can be used to stabilize nano-Pt particles. The fuel cell performance is not improved over a suitable control electrode. If the correct HPA is used it appears that significant advantages can be obtained in fuel cell catalyst layer stability. Stability over 4000 cycles has been achieved. Encouragingly the F- emission rates from the MEA can be dramatically reduced.

We describe a new class of materials for proton conduction for proton exchange membrane (PEM) fuel cell applications based on the heteropoly acids (HPAs). HPAs are readily functionalized by a variety of moieties including polymerizable organic groups. These hybrid monomers are polymerized into polypolyoxometallates (polyPOMs). The materials are characterized by IR, NMR, and SAXS. Proton diffusion coefficients are measured by Pulse Field Gradient Spin Echo NMR and are observed to increase with temperature. In-plane proton conductivity measurements show that performance similar to a state-of-the-art PFSA ionomer is obtained at 80 {degree sign}C and 100% RH. Conductivities at lower RH or higher temperature are not yet sufficiently high. For these first generation materials many problems still need to be addressed in order to fabricate materials with all the required properties for a next generation PEM.

The use of heteropoly acids (HPAs) in PEM fuel cell anode catalyst layers was studied. To compare the doped electrodes with a control electrode in a meaningful way membrane electrode assemblies (MEAs) were prepared with two 1/2 anodes, one the undoped control and one the test electrode. This ensured that both the control and test electrode were subject to the same thermal and electrochemical history. After curve fitting the data using a least squares method the error was found to be 1% in E 0 , 25% in the Tafel slope and 15% in the area specific resistance. The electrodes used were commercial electrodes of the Los Alamos type (ELATs). Doping a fuel cell anode with H 5 PMo 10 V 2 O 40 resulted in a fourfold increase in the area specific resistance of the MEA, but the performance was not equivalent to that of an anode incorporating Nafion ® . Doping H 5 PMo 10 V 2 O 40 in Nafion ® painted ELATs resulted in negligible improvements in the performance compared to ELATs incorporating only Nafion ® . Much more impressive was the improvement in maximum power from doping the Nafion ® painted ELAT with H 7 [P 2 W 17 O 61 (Fe III ·OH 2 )] or H 12 [(P 2 W 15 O 56 ) 2 Fe 4 III (H 2 O) 2 ]. Eighty-five percent improvements in maximum power and 100% improvements in area specific resistance were observed from this HPA doped ELAT.

Free acids of the iron substituted heteropoly acids (HPA), H 7 [(P 2 W 17 O 61 )Fe III (H 2 O)] (HFe1) and H 18 [(P 2 W 15 O 56 ) 2 Fe III 2 (H 2 O) 2 ] (HFe2) were prepared from the salts K 7 [(P 2 W 17 O 61 )Fe III (H 2 O)] (KFe1) and Na 12 [(P 2 W 15 O 56 ) 2 Fe III 4 (H 2 O) 2 ] (NaFe4), respectively. The iron-substituted HPA were adsorbed on to XC-72 carbon based GDLs to form HPA doped GDEs after water washing with HPA loadings of ca . 1 μmol. The HPA was detected throughout the GDL by EDX. Solution electrochemistry of the free acids are reported for the first time in sulfate buffer, pH 1–3. The hydrogen oxidation reaction was catalyzed by KFe1 at 0.33 V, with an exchange current density of 38 mA/cm 2 . Moderate activity for the oxygen reduction reaction was observed for the iron substituted HPA, which was dramatically improved by selectively removing oxygen atoms from the HPA by cycling the fuel cell cathode under N 2 followed by reoxidation to give a restructured oxide catalyst. The nanostructured oxide achieved an OCV of 0.7 V with a Tafel slope of 115 mV/decade. Cycling the same catalysts in oxygen resulted in an improved catalyst/ionomer/carbon configuration with a slightly higher Tafel slope, 128 mV/decade but a respectable current density of 100 mA/cm 2 at 0.2 V.

Proton exchange membranes were cast from mixtures of the 3M perfluorinated sulfonic acid ionomer, with side chain -O-(CF2) 4-SO3H, and various heteropoly acids (HPAs) at a 10 or 20 wt% doping level. The membrane electrode assemblies (MEAs) prepared from these membranes were subjected to a fuel cell testing protocols involving incubation to steady state, temperature challenge, accelerated testing, and post mortem analysis. The cell temperature was varied from 70 - 100 ºC under relatively dry conditions, 70 ºC dewpoint, to avoid leaching of the HPA. The most important finding from this study was that the more stable HPAs, H4SiW12O40, α-H3P2W18O62, and H6P2W21O71 reduce the rate of F- release threefold and improve the performance of the MEA dramatically under these conditions. For HPAs that possibly rearrange in peroxide or at elevated temperatures, H3PW12O40, H6CoW12O40, H5SiAlW11O39, H6As2W21O69, and H21B3W39O162, the results were mixed as fragments of these molecules possibly interfere with the fuel cell electrochemistry.

Very small amounts of various vanadium or iron substituted Heteropoly acids (HPA) are strongly adsorbed on to commercial XC-72R based carbon gas diffusion electrodes. The electrochemical activity of these adsorbed HPA for both the hydrogen oxidation reaction and the oxygen reduction reaction is investigated as non-platinum electro-catalysts and it is shown that these materials have a moderate activity at the extremely low doping levels achieved. On the cathode rearrangement of the precursor HPA induced by moderate heating (vanadium) or cycling the fuel cell in the absence of oxygen (iron) occurs to give a more active electro-catalyst. The HPA studied are also proposed for use in CO tolerant anodes and as mixed electronic/protonic conductors in platinized fuel cell electrodes.

Perfluorinated sulfonic acid (PFSA) membranes have long been the standard for proton exchange membranes (PEMs), despite many efforts to improve upon their chemistry. The saturated conductivity of these PFSAs is impressive, but a need still exists for a membrane with similar proton conductivity at low relative humidities.1 The motivation of this study was to optimize the loading of heteropolyacid (HPA) covalently bonded to the fluoroelastomer in order to increase low humidity conductivity while maintaining chemical and mechanical stability. HPAs are known to be strong Brønsted acids as well as strong oxidants and have high thermal stability in the solid state.2 These qualities should serve to effect enhanced proton conductivity and chemical durability at high temperature ranges (80 - 120 ºC) and lower humidity ranges (less than saturated conditions). Specifically, a Keggin-type silica tungstic HPA was used for its comparative stability to hydrolysis in aqueous solutions.3 In order to classify membrane behavior as a function of weight percent polyHPA (reference figure 1), membranes were synthesized in 0 wt%, 25 wt%, 50 wt%, 75 wt%, and 100 wt% polyHPA and the balance PFSA. Electrochemical impedance spectroscopy (EIS) was used to characterize conductivity of the membranes at 80 ºC with a relative humidity sweep (50 - 90 %RH). Additionally, small-angle x-ray scattering (SAXS) was performed at 80 °C with a relative humidity sweep from 0 - 95 %RH, and FTIR was performed at 80 °C at 0 %RH and 100 %RH. These conditions were chosen specifically for the typical operating region for PEMFC applications. In this blend study, the addition of polyHPA was found to categorically decrease performance (conductivity) of standard 3M© 825EW PFSA membrane. Though improvement of the PFSA membrane was not achieved, this research will provide valuable information regarding the morphology of blended membranes, particularly in membranes exhibiting two-phase behavior; furthermore, results will provide some insight into choosing other viable additives for improved conductivity of PEMFCs. Figure 1. Chemical structure of polyHPA, 60 wt% HPA (K8SiW11O39) References Ramani, V., H.R. Kunz, and J.M. Fenton. "Investigation Of Nafion®/HPA Composite Membranes For High Temperature/Low Relative Humidity PEMFC Operation". Doi.org. N.p., 2017. Web. 24 Apr. 2017. Kozhevnikov, I.V., and K.I. Matveev. "Homogeneous Catalysts Based On Heteropoly Acids (Review)". Applied Catalysis 5.2 (1983): 135-150. Web. Tsigdinos, G.A., and G.H. Moh. "Aspects Of Molybdenum And Related Chemistry". Materials Chemistry 4.1 (1979): 111-112. Web. Figure 1

While perfluorinated sulfonic acids (PFSA)s have many desirable qualities for use as a membrane separator in a polymer electrolyte membrane fuel cell (PEMFC), they suffer from decomposition via radical attack and excessive swelling. These two properties reduce the chemical and mechanical durability, respectively, of PFSA materials in the operating environment of a fuel cell. Through using heteropoly acids (HPA)s as an ion-conducting, crosslinking moiety, these short comings of PFSA membranes can be overcome. HPAs are known to be highly conductive [1] and are able to react with radicals. Our approach is to use a commercially available fluoroelastomer and functionalizes using HPA crosslinks. First, FC-2178 (polyvinylidene-co-hexafluoropropylene) is functionalized with phosphonic acid containing sidechains. Next, lacunary silicotungstic acid is covalently bonded to acidic sicechains. This material is stable in aqueous environments, unlike blends of HPA and PFSA. The results of in-situ evaluation of these membranes show impressive durability in accelerated stress test (AST). The loss of open circuit voltage (OCV) in the chemical degradation test is much less than traditional films, resulting in >0.8V OCV after 500 hrs. Also, the minimal swelling of this material leads to greater durability in humidity cycling ASTs with negligible H2 crossover after 20,000 dry wet cycles. Overall, this material shows great promise in outperforming PFSAs in chemical and mechanical ASTs. References: [1] Nakamura, O.; Kodama, T.; Ogino, I.; Miyake, Y., High-Conductivity Solid Proton Conductors - Dodecamolybdophosphoric Acid and Dodecatungstophosphoric Acid Crystals. Chemistry Letters 1979, 17-18.