Showing papers on "Nafion published in 2014"
TL;DR: In this article, an ion-aggregating highway was constructed in the alkaline polymer electrolytes (APEs), such that the OH− conduction becomes as efficient as the H+ conduction in Nafion (greater than 0.1 S cm−1 at 80 °C under moderate ion exchange capacity.
Abstract: Alkaline polymer electrolytes (APEs) are an emerging material that enables the use of nonprecious-metal catalysts in electrochemical energy technology, such as fuel cell and water electrolysis. Yet the OH− conduction in APE has been of much lower efficiency than the H+ conduction in its acidic counterpart (typically Nafion), leading to a large dissipative loss in energy conversion applications. Here we report that, by properly constructing ion-aggregating structures in APE, a OH− conducting highway can be built, such that the OH− conduction in APE becomes as efficient as the H+ conduction in Nafion (greater than 0.1 S cm−1 at 80 °C under moderate ion-exchange capacity 1.0 mmol g−1). The optimal approach to constructing such an ionic highway is first screened computationally using coarse-grained molecular dynamics (CGMD) simulations, and then implemented experimentally based on a quaternary ammonia polysulfone (QAPS) model system. The resulting ordered structure of ion assembly has been unambiguously revealed by both the theoretically calculated structure factor and experimental results of TEM and SAXS. These findings have not only furthered our understanding about the ionic channels in APE, but also provided a general strategy for the rational design of polymer electrolytes.
432 citations
TL;DR: In this article, the importance of ion/solvent, residual ion/ion, and solvent/polymer interactions for the formation and mobility of ionic charge carriers and selective ionic transport is emphasized, and it is shown that, apart from simple electrostatics, specific chemical interactions must be considered.
Abstract: Transport and stability issues of proton and hydroxide ion conducting separator membranes for fuel cells are critically discussed from a fundamental point of view. Considerations of structure and dynamics on the molecular scale to the device level equally imply polymer-chemical and electrochemical aspects which are closely related for this class of materials. The importance of ion/solvent, residual ion/ion, and solvent/polymer interactions for the formation and mobility of ionic charge carriers and selective ionic transport and even as driving forces for nanoscale ordering is emphasized, and it is shown that, apart from simple electrostatics, specific chemical interactions must be considered. On the basis of this understanding, suggestions are being made for the modification of existing and the development of new membrane types, not only for fuel cells but also for other electrochemical energy conversion and storage devices such as redox-flow and alkaline ion batteries.
374 citations
TL;DR: The analyses reveal that doubling the amount of Nafion in the electrode leads to a twofold increase in its degree of coverage of the carbon, while the thickness of the layer, around 7 nm, is unchanged.
Abstract: Proton exchange membrane fuel cell is one of the most promising zero-emission power sources for automotive or stationary applications. However, their cost and lifetime remain the two major key issues for a widespread commercialization. Consequently, much attention has been devoted to optimizing the membrane/electrode assembly that constitute the fuel cell core. The electrodes consist of carbon black supporting Pt nanoparticles and Nafion as the ionomer binder. Although the ionomer plays a crucial role as ionic conductor through the electrode, little is known about its distribution inside the electrode. Here we report the three-dimensional morphology of the Nafion thin layer surrounding the carbon particles, which is imaged using electron tomography. The analyses reveal that doubling the amount of Nafion in the electrode leads to a twofold increase in its degree of coverage of the carbon, while the thickness of the layer, around 7 nm, is unchanged. In proton exchange membrane fuel cells, little is known about distribution of ionomers inside electrodes. Here, the authors present an electron tomography technique that allows a three dimensional visualization and quantitative analysis of ionomer layers in the electrodes.
263 citations
TL;DR: A series of novel composite membranes, based on sulfonated poly(ether ether ketone) (SPEEK) with various graphene oxide (GO) loadings, were employed and investigated in vanadium redox flow battery (VRFB) for the first time as discussed by the authors.
Abstract: A series of novel composite membranes, based on sulfonated poly(ether ether ketone) (SPEEK) with various graphene oxide (GO) loadings, were employed and investigated in vanadium redox flow battery (VRFB) for the first time. The scanning electron microscopy images of the composite membranes revealed the uniform dispersion of GO nanosheets in the polymer matrix due to the interaction between GO and SPEEK, as confirmed by Fourier transform infrared spectra. The mechanical and thermal parameters of the composite membranes increased, while the VO2+ permeability decreased with increasing GO content. Random embedding of GO nanosheets in the membranes can serve as effective barriers to block the transport of vanadium ion, resulting in a significant decrease of vanadium ion permeability. The VRFB assembled with the composite membrane exhibited highly improved cell parameters and strikingly long cycling stability compared with commercial Nafion 117 membrane. With the protection of porous PTFE substrate, the pore-filling SPEEK/GO composite membrane based on VRFB ran for 1200 cycles with relatively low capacity decline.
222 citations
TL;DR: In this paper, in-situ Pt-graphene (Pt-G) nanoparticles were applied to graphene oxide (GO) using a microwave method, finally resulting in Pt-G composite membrane.
169 citations
TL;DR: In this study, phytic acid was first immobilized by MIL101 via vacuum-assisted impregnation method and utilized as a novel filler to incorporate into Nafion to fabricate hybrid proton exchange membrane for application in PEMFC under different relative humidities (RHs), especially under low RHs.
Abstract: In this study, phytic acid (myo-inositol hexaphosphonic acid) was first immobilized by MIL101 via vacuum-assisted impregnation method. The obtained phytic@MIL101 was then utilized as a novel filler to incorporate into Nafion to fabricate hybrid proton exchange membrane for application in PEMFC under different relative humidities (RHs), especially under low RHs. High loading and uniform dispersion of phytic acid in MIL 101(Cr) were achieved as demonstrated by ICP, FT-IR, XPS, and EDS-mapping. The phytic@MIL101 was dispersed homogeneously in the Nafion matrix when the filler content was less than 12%. Hybrid membranes were evaluated by proton conductivity, mechanical property, thermal stability, and so forth. Remarkably, the Nafion/phytic@MIL hybrid membranes showed high proton conductivity at different RHs, especially under low RHs, which was up to 0.0608 S cm–1 and 7.63 × 10–4 S cm–1 at 57.4% RH and 10.5% RH (2.8 and 11.0 times higher than that of pristine membrane), respectively. Moreover, the mechanical...
163 citations
TL;DR: In this article, the properties of Nafion, a prototypical ionomer, are investigated as thin films (4 to 300 nm) on carbon, gold, and platinum substrates that are fabricated using different casting methods and thermal histories.
Abstract: Thin films of ion-conducting polymers are an important area of study due to their function in many electrochemical devices and as analogues for interfacial phenomena that occur in bulk films. In this paper, the properties of Nafion, a prototypical ionomer, are investigated as thin films (4 to 300 nm) on carbon, gold, and platinum substrates that are fabricated using different casting methods and thermal histories. Specifically, water uptake, swelling, and morphology are investigated by quartz-crystal microbalance, ellipsometry, and grazing-incidence X-ray scattering to develop structure/property/processing relationships. For all substrates, as the films' thickness decreased, there is an initial decrease in swelling followed by a subsequent increase for film thicknesses below ≈20 nm due to a disordering of the film hydrophilic/hydrophobic structure. Decreased swelling and less structural order is observed on gold for spin-cast films compared to self-assembled films; the opposite effect is observed for films on carbon. The presented systematic data set and analyses represent a thorough study of the behavior of Nafion thin films on model substrates of interest in metal catalyst/carbon electrodes, and these insights help to elucidate the underlying polymer physics and confinement effects in these and related systems.
162 citations
TL;DR: Because of the good balance of proton conductivity and vanadium ion permeability, blend membrane with 20 wt % PAN (S/PAN-20%) showed higher Coulombic efficiency and energy efficiency than Nafion 117 membrane when they were used in VRFB single cell.
Abstract: Acid–base blend membrane prepared from sulfonated poly(ether ether ketone) (SPEEK) and polyacrylonitrile (PAN) was detailedly evaluated for vanadium redox flow battery (VRFB) application. SPEEK/PAN blend membrane exhibited dense and homogeneous cross-section morphology as scanning electron microscopy and energy-dispersive X-ray spectroscopy images show. The acid–base interaction of ionic cross-linking and hydrogen bonding between SPEEK and PAN could effectively reduce water uptake, swelling ratio, and vanadium ion permeability, and improve the performance and stability of blend membrane. Because of the good balance of proton conductivity and vanadium ion permeability, blend membrane with 20 wt % PAN (S/PAN-20%) showed higher Coulombic efficiency (96.2% vs 91.1%) and energy efficiency (83.5% vs 78.4%) than Nafion 117 membrane at current density of 80 mA cm–2 when they were used in VRFB single cell. Besides, S/PAN-20% membrane kept a stable performance during 150 cycles at current density of 80 mA cm–2 in t...
153 citations
TL;DR: In this article, the authors studied the transport of water and anions (OH−, HCO3−, F−, Cl−, Br−, and I−) in poly(arylene ether) anion exchange membrane with quaternary ammonium functional groups.
152 citations
TL;DR: In this article, a low cost sulfonated poly (ether ether ketone) membranes have been successfully prepared and optimized at various sulfonation conditions by casting method for vanadium redox battery applications.
148 citations
TL;DR: In this article, the authors investigated the transport properties of Nafion nanothin films and found that the proton conductivity and capacitance of the thin films are thickness-dependent.
Abstract: TheprotontransportpropertyofNafionnanothinfilms (4‐300nm)hasbeeninvestigatedbyelectrochemical impedancespectroscopy (EIS)usinginterdigitatedarray(IDA)ofgoldelectrodesonSiO2 substrate.Theprotonconductivityhasbeeninvestigatedasafunction of film drying/heating protocol, relative humidity, temperature and film thickness. It is found that the film treatment protocol makes a difference in film transport property. Ultimately, the proton conductivity and capacitance of the Nafion nanothin film is thicknessdependent,wheretheformerdecreased andthelatterincreasedexponentiallywithdecreasingfilmthickness.Moreover,theactivation energy increased exponentially with decreasing film thickness. The proton conductivity of the thin films of Nafion is significantly lower than that of the membrane counterpart regardless of the thickness, which is consistent with the high activation energy found in the thin films. These differences are likely related to the polymer confinement and morphological differences between the thin films and the freestanding membrane. © The Author(s) 2014. Published by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any
TL;DR: In this article, a 9-cell proton exchange membrane (PEM) water electrolysis stack was developed and tested for 7800 h and the average degradation rate of 35.5 m Vh 1 per cell was measured.
TL;DR: In this article, a 3-step reaction route for the preparation of poly(vinylidene fluoride) electrospun nanofibers (PVDFNF-Nafion) has been described.
Abstract: Nafion-functionalized poly(vinylidene fluoride) electrospun nanofibers (PVDFNF-Nafion) have been prepared through a 3-step reaction route. The chemical structure of PVDFNF-Nafion is characterized with Fourier transform infrared and X-ray photoelectron spectroscopy. Functionalization with Nafion chains improves the interfacial compatibility between the PVDF-based nanofibers and Nafion matrix in formation of PVDFNF-Nafion reinforced Nafion composite membrane (Nafion-CM1). Aggregation of Nafion chains on the nanofiber surfaces induces the formation of proton-conducting channels so as to increase the proton conductivity of the Nafion-CM1 membrane. In the H2/O2 single cell test, Nafion-CM1 shows a maximum power density of 700 mW cm−2 which is higher than the value of 500 mW cm−2 recorded with commercial Nafion 212 membrane. The presence of PVDFNF-Nafion also depresses the methanol permeability of the Nafion-CM1 membrane with alteration of the crystalline domains of Nafion. In direct methanol fuel cell tests, the low methanol permeability of Nafion-CM1 means it could be operated with 5 M methanol as the fuel and exhibits a maximum power density of 122 mW cm−2, which is larger than the value (60 mW cm−2) recorded with commercial Nafion 117 membrane and 2 M methanol fuel.
TL;DR: In this article, a novel composite membrane of sulfonated poly(ether ether ketone) (SPEEK) and graphene was prepared and investigated, which revealed the presence and the uniformity dispersion of graphene in the SPEEK matrix.
TL;DR: In this paper, sulfonated graphene oxide-silica (S-GO-SiO2) nanohybrid particles were obtained first and the FTIR, TGA, XRD, Raman, AFM, FE-SEM and EDX characterizations were employed to confirm the successful decoration of SiO2 onto GO surface and the attachment of sulfonic acid groups onto the GO−SiO 2 surface.
Abstract: In the current study, sulfonated graphene oxide–silica (S-GO–SiO2) nanohybrid particles were obtained first. The FTIR, TGA, XRD, Raman, AFM, FE-SEM and EDX characterizations were employed to confirm the successful decoration of SiO2 onto GO surface and the attachment of sulfonic acid groups onto the GO–SiO2 surface. Then, S-GO–SiO2/Nafion proton exchange membranes (PEMs) were prepared via solution casting. S-GO–SiO2 had a good dispersibility inside the membrane matrix. The increased water uptake and the incorporated –SO3H groups bestowed a large increase in proton conductivity upon these composite PEMs. Meanwhile, the barrier effect of two-dimensional S-GO–SiO2 contributed to the obvious reduction in methanol permeability of the composite PEMs, as a result of the increased tortuosity of the transport channels. Therefore, novel S-GO–SiO2/Nafion PEMs with enhanced selectivity (the ratio of proton conductivity to methanol permeability) were obtained. Even under harsh conditions, such as high methanol concentration and/or increased temperature, the membrane selectivity of S-GO–SiO2/Nafion composite membranes was still nearly two-orders-of-magnitude higher than that of the recast Nafion membrane. It renders this type of composite PEMs a very promising candidate for the application in DMFC. All the conclusions were demonstrated by various characterizations, such as (FE-) SEM, TEM, AFM, FTIR, TGA, water uptake, etc.
TL;DR: In this article, a non-enzymatic amperometric glucose sensor based on CuO nanoparticles and a graphene nanocomposite was developed for glucose detection in blood samples.
Abstract: A new and simple method was introduced for the preparation of a non-enzymatic amperometric glucose sensor based on CuO nanoparticles–graphene nanocomposite. Differential pulse voltammetry, cyclic voltammetry and electrochemical impedance spectroscopy were used for the evaluation of the prepared sensors. The synthesized graphene and CuO nanoparticles were dispersed in DMF/H 2 O (90:10) solvent mixture and then a little amount of the suspension was drop-coated on the surface of a glassy carbon electrode. It was found that the kind of solvent, utilized for the dispersion of graphene and CuO nanoparticles, had very crucial effect on both sensitivity and reproducibility of the prepared sensor. The nanocomposite coating thickness and CuO/graphene mass ratio were optimized to achieve the best sensitivity. A synergistic effect was substantiated between graphene and CuO nanoparticles for electro-catalytic oxidation of glucose. Dependence of the sensor response to glucose concentration was dynamically linear between 0.5 and 2000 μmol L −1 and at this concentration range the optimized sensor represented very high sensitivity (2939.24 μA mM −1 cm −2 ). Moreover, the detection limit of 0.09 μmol L −1 was calculated for this sensor. The sensor was properly utilized for glucose assay in blood samples.
TL;DR: Organic electrochemical transistors (OECTs) are successfully used as highly sensitive and selective dopamine sensors and are suitable for low-cost and disposable sensing application.
Abstract: Organic electrochemical transistors (OECTs) are successfully used as highly sensitive and selective dopamine sensors. The selectivity of the OECT-based dopamine sensors is significantly improved by coating biocompatible polymer Nafion or chitosan on the surface of the gate electrodes. The interference induced by uric acid and ascorbic acid is effectively eliminated especially after the modification of Nafion. The sensitivity of the devices is improved by graphene flakes co-modified on the gate electrodes. The detection limit of the devices to dopamine is down to 5 nM, which is much lower than that of conventional electrochemical approaches. Because the OECT-based dopamine sensors are solution processable, they are suitable for low-cost and disposable sensing application.
TL;DR: The combination of the direct transduction of peptide cleavage events with the highly sensitive ECL method is a promising strategy for the design of enzymatic cleavage-based ECL biosensors with high sensitivity and selectivity.
Abstract: A novel electrogenerated chemiluminescence peptide-based biosensor (ECL-PB) for the determination of prostate-specific antigen (PSA) was developed on the basis of target-induced cleavage of a specific peptide within Nafion film incorporated with gold nanoparticles (AuNPs) and ECL emitting species. A specific peptide (CHSSKLQK) was used as a molecular recognition element; tris(2,2′-ripyridine) dichlororuthenium(II) (Ru(bpy)32+) was used as ECL emitting species, and ferrocene carboxylic acid (Fc) was employed as ECL quencher. The ECL-PB biosensor was fabricated by casting the mixture of Nafion and AuNPs onto the surface of glassy carbon electrode to form AuNPs/Nafion film, and then, Ru(bpy)32+ was electrostatically adsorbed into the AuNPs/Nafion film; finally, the peptide-tagged with ferrocene carboxylic acid (Fc-peptide) was self-assembled onto the surface of the AuNPs. When PSA was present, it specifically cleaved the Fc-peptide, leading the quencher to leave the electrode and resulting in the increase of...
TL;DR: In this paper, the advantages and disadvantages of SSAS vs the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level, are discussed.
Abstract: Developed in the early 1900's, the “Haber-Bosch” synthesis is the dominant NH3 synthesis process. Parallel to catalyst optimization, current research efforts are also focused on the investigation of new methods for ammonia synthesis, including the electrochemical synthesis with the use of solid electrolyte cells. Since the first report on Solid State Ammonia Synthesis (SSAS), more than 30 solid electrolyte materials were tested and at least 15 catalysts were used as working electrodes. Thus far, the highest rate of ammonia formation reported is 1.13×10−8 mol s−1 cm−2, obtained at 80°C with a Nafion solid electrolyte and a mixed oxide, SmFe0.7Cu0.1Ni0.2O3, cathode. At high temperatures (>500oC) the maximum rate was 9.5*10-9 mol s−1 cm−2 using Ce0.8Y0.2O2-δ -[Ca3(PO4)2 -K3PO4] as electrolyte and Ag-Pd as cathode. In this paper, the advantages and the disadvantages of SSAS vs the conventional process and the requirements that must be met in order to promote the electrochemical process into an industrial level, are discussed.
TL;DR: In this paper, an excellent electrochemical sensor based on Nafion/multi-walled carbon nanotubes/carbon dots/multiwalled carbonnanotubes for simultaneous determination of hydroquinone (HQ), catechol (CC) and resorcinol (RS) in 0.1 mM phosphate buffer solutions (PBS, pH = 7.0) was found.
TL;DR: In this paper, a nafion-coated electrode was used to improve the performance of lithium sulfur batteries and achieved an initial discharge capacity of 1084 mAhg−1, with a Columbic efficiency of about 100%.
TL;DR: In this paper, the effects of microstructure of Sn catalyst layer on the Faradaic efficiency towards formate formation as a function of Nafion loading, thickness of the catalyst layer, and catalyst particle size were reported.
TL;DR: The remarkably high performance of the Nafion composite membrane was mainly attributed to the reduction of ohmic resistance by the mesoporous hygroscopic metal oxide nanotubes, which can retain water and effectively enhance water diffusion through the membrane.
Abstract: We describe a facile route to fabricate mesoporous metal oxide (TiO2, CeO2 and ZrO1.95) nanotubes for efficient water retention and migration in a Nafion membrane operated in polymer electrolyte fuel cell under low relative humidity (RH). Porous TiO2 nanotubes (TNT), CeO2 nanotubes (CeNT), and ZrO1.95 (ZrNT) were synthesized by calcining electrospun polyacrylonitrile nanofibers embedded with metal precursors. The nanofibers were prepared using a conventional single spinneret electrospinning technique under an ambient atmosphere. Their porous tubular morphology was observed by SEM and TEM analyses. HR-TEM results revealed a porous metal oxide wall composed of small particles joined together. The mesoporous structure of the samples was analyzed using BET. The tubular morphology and outstanding water absorption ability of the TNT, CeNT, and ZrNT fillers resulted in the effective enhancement of proton conductivity of Nafion composite membranes under both fully humid and dry conditions. Compared to a commercia...
TL;DR: In this paper, the degradation mechanism of Nafion/PTFE composite membrane in PEM fuel cell with intensive RH cycling and load cycling was investigated and it was recognized that the edge of membrane electrode assembly should be carefully treated to prevent the immediate failure for excessive or non-uniform mechanical stress mainly caused by RH cycling in the early period of ASTs.
TL;DR: In this paper, a photoelectrochemical cell for water electrolysis is applied to the case of light-absorbing particles embedded in a membrane separator, and the maximum iH2,net is calculated to be 6.97 mA cm−2 at RH = 30%.
Abstract: A fully integrated model of a photoelectrochemical cell for water electrolysis is applied to the case of light-absorbing particles embedded in a membrane separator. Composition of the product gases is shown to be one critical measure of device performance. Not only must the composition be kept outside the explosive window for mixtures of H2 and O2, but also product purity is a concern. For the absorber-in-membrane geometry and the model assumptions used here, results show purely water-saturated H2 on the cathode side and water-saturated O2 on the anode side. Since it is possible to design devices that violate these assumptions, it should not be assumed that a polymer separator or an absorber-in-membrane geometry will be effective in preventing explosive mixtures in all cases. Net H2 collected, iH2,net, is the second essential performance metric, and it is shown to differ significantly from the more commonly reported total H2 produced and operating current density. Schemes which co-evolve H2 and O2 violate the first metric and do not provide the second. A composite of triple-junction silicon absorbers in a Nafion membrane is shown to have an optimum thickness of 30 μm, dependent on the properties of the light absorber. Varying membrane properties reveals a tradeoff between conductivity, κm, and gas permeabilities, ψH2 and ψO2, that can potentially be exploited differently than in a fuel cell. Modulating the relative humidity (RH) is insufficient. The maximum iH2,net is calculated to be 6.97 mA cm−2 at RH = 30% relative to a value of 6.92 mA cm−2 at RH = 100%. The model identifies target material properties for new polymers. If ψ is dropped one order of magnitude below that of Nafion (ψ/ψNafion = 0.1), the optimum value for iH2,net increases by 63.5%. For ψ/ψNafion = 0.01, the optimum iH2,net increases by 73.5%, which compares favorably to the 74.5% improvement that would result if Nafion were made impermeable (ψ/ψNafion = 0). Meanwhile, κm can drop to a value of 1.2 × 10−3 S cm−1 (two orders of magnitude below liquid-equilibrated Nafion) with less than a 5% decline in iH2,net.
TL;DR: In this paper, a sulfonated graphene and polypyrrole (PPy) nanocomposite was synthesized by interfacial polymerization and a supercapacitor was fabricated by dispersing PPy/SG composite in nafion solution and coated on a stainless steel net.
Abstract: A novel electrode material for a supercapacitor has been developed based on a sulfonated graphene (SG) and polypyrrole (PPy) nanocomposite synthesized by interfacial polymerization. Characterizations of the synthesized composites are performed by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscope (TEM) techniques. The composites showed noticeable improvements in electrical conductivity and excellent electrochemical reversibility. The supercapacitor is fabricated by dispersing PPy/SG composite in nafion solution and coated on a stainless steel net. The composite revealed a maximum value of capacitance of 360 F g–1 at a current density of 1 A g–1. This simple method is suitable for developing a variety of SG based composites for applications in energy storage devices.
TL;DR: In this paper, the effect of thermal annealing on pertinent ionomer-film properties: proton transport and surface wettability was reported, and it was found that both surface and bulk rearrangement/reorganization occur simultaneously upon anneal.
Abstract: The ionomer in the catalyst layer of polymer electrolyte fuel cells exists as ultrathin films (4–10 nm) covering the aggregates of Pt/C catalyst and may experience elevated temperatures during hot-pressing step of the electrode fabrication process. In this study, we report the effect of thermal annealing on pertinent ionomer-film properties: proton transport and surface wettability. Self-assembled, 10 nm thin Nafion ionomer films on silica substrate were heat treated at different temperatures in the range 40–160 °C. It was found that both surface and bulk rearrangement/reorganization occur simultaneously upon annealing. Surface reorganization was evident by the dramatic change in free-surface wettability from super-hydrophilic to hydrophobic. On the other hand, bulk rearrangement was evident from significant depression in the proton conductivity with increasing treatment temperature. Extended exposure, up to 18 h, to water in vapor form at high humidity did not change the protonic conductivity. On the oth...
TL;DR: In this paper, the electrical, mechanical, and compositional characterization of a graphene oxide membrane is presented, and its application as an electrolyte material in a polymer electrolyte membrane fuel cell is explored.
TL;DR: Nanoporous (NP) PtAu alloy is easily fabricated by a simple and general dealloying method, and it exhibits excellent amperometric durability and long-term stability for H2O2 and glucose as mentioned in this paper.
Abstract: Nanoporous (NP) PtAu alloy is easily fabricated by a simple and general dealloying method. Characterized by three-dimensional nanospongy architecture with a typical dimension around 5 nm, the as-prepared NP-PtAu alloy shows superior sensing performance towards glucose and hydrogen peroxide (H2O2) with highly sensitive response compared with commercial Pt/C and NP-Pt catalysts. Importantly, NP-PtAu exhibits excellent amperometric durability and long-term stability for H2O2 and glucose. After coating additional nafion on the working electrode, NP-PtAu shows a good anti-interference towards ascorbic acid, uric acid, and dopamine during glucose detection. NP-PtAu alloy holds great application potential for electrochemical sensing with simple preparation, high catalytic activity, and high structure stability.
TL;DR: In this article, the use of partially sulfonated polyaniline, as the second component, produced selectivity ratio of 5.85 × 105 × 105 − Ss−cm−3, ion exchange capacity of 0.71 ǫg−1, and current density of 90.5 mW cm−2 at +0.2 V and 60°C and corresponding maximum power density of 18.5mWcm−2.