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A proton exchange membrane (PEM) is one of the most critical and expensive components in a dual‐chamber microbial fuel cell (MFC) that separates the anode and cathode chambers. The novel macroporous kaolin earthenware coated with polybenzimidazole (NKE‐PBI) fabricated in this study could become an alternative to PEM membranes. Briefly, PBI powder was dissolved in dimethylacetamide. Thereafter, NKE was fabricated at different porosities (10%, 20%, and 30%) using different starch powder volumes, which acted as pore‐forming agents. The NKE‐PBI with 30 vol% starch powder content produced the highest power output of 2450 ± 25 mW m−2 (10.50 A m−2) and internal resistance of 71 ± 19 Ω under batch mode operation. The MFC–PEM reactor generated the lowest power output at the highest internal resistance of up to 1300 ± 15 mW m−2 (3.7 A m−2) and 313 ± 16 Ω, respectively. In this study, the nonselective porous NKE coated with PBI membranes improved proton conduction activity and displayed comparable power performance with that of Nafion 117 in a dual‐chambered MFC. Therefore, a porous earthenware membrane coated with a proton conductor could become a potential separator in a scaled‐up MFC system for commercialization.

Lanthanum orthoantimonate was synthesized using a solid-state synthesis method. To enhance the possible protonic conductivity, samples with the addition of 1 mol % Ca in La-site were also prepared. The structure was studied by the means of X-ray diffraction, which showed that both specimens were single phase. The materials crystallized in the space group P21 /n. Dilatometry revealed that the material expanded non-linearly with the temperature. The nature of this deviation is unknown; however, the calculated linear fraction thermal expansion coefficient was 9.56×10-6 K-1 . Electrical properties studies showed that the material is a proton conductor in oxidizing conditions, which was confirmed both by temperature studies in wet in dry air, but also by the H/D isotope exchange experiment. The conductivity was rather modest, peaking at the order of 10-6 S cm-1 at 800 °C, but this could be further improved by microstructure and doping optimization. This is the first time protonic conductivity in lanthanum orthoantimonates is reported.

Y-doped BaZrO3 , BaCeO3 and BaZr1-x Cex O3 show high proton conductivity at intermediate temperature and are promising electrolyte candidates in electrochemical devices. However, in most cases, the present cell fabrication process seems to be unavailable to avoid the addition of NiO, which is either added to improve the sinterability of these electrolyte or diffuses from the electrode substrate during co-sintering. In this work, a systematic investigation was performed to study the effect of NiO on BaZr0.8-x Cex Y0.2 O3-δ (BZCY20) covering the full Ce range from 0 to 0.8. The results revealed that regardless of the composition of BZCY20, both the dehydration temperature and proton concentration decreased by adding NiO, which further greatly decreased the ionic conductivity and the transport number. And it is found that the redox cycles in Ce-rich samples containing Ni makes the grain boundary conductivity worse and the electrolyte brittle. The conclusion is that NiO is detrimental to the performance of the electrochemical cells using these materials as the electrolyte, although compromise might be achieved in certain degree by tuning the Ce content. However, it should be noted that to further improve the cell performance, a new sintering additive or new processing for cell fabrication is essential.

Cross‐linking of phosphoric acid doped polybenzimidazole membranes as fuel cell electrolytes represents an attractive approach to improving the mechanical robustness at a high acid loading. Numerous cross‐linking concepts have been reported in the literature, but a deeper understanding of how the cross‐linking chemistry affects the physicochemical properties of the membrane and its fuel cell performance and durability remains to be assessed. In this work, a series of cross‐linked membranes are prepared using cross‐linking agents of different regio‐chemistry and steric nature. It is shown, that the nature of the cross‐linking agent has a large impact on the effective degree of cross‐linking, which in turn determines the acid doping characteristics and ultimately the fuel cell performance and acid retention during long‐term operation.

π-π stacking between GO and Benzene sulfonic acid (BS) / Naphthalene sulfonic acid (NS) / Pyrene sulfonic acid (PS) / Naphthalene disulfonic acid (ND) has resulted in the respective GO-BS, GO-NS, GO-PS and GO-ND proton conductive hybrid. The conductivity follows the trend as GO-NS ˃ GO-BS ˃ GO-PS ˃ GO ˃ GO-ND. GO-NS possesses the maximum interlayer distance with exhibiting seven times higher proton conductivity compared with GO. Evidently, π-π stacking of sulfonic acid derivatives with GO can adopt it as superionic conductor.

A new proton conducting fuel cell design based on the BZCYYb electrolyte is studied in this research. In high performance YSZ based SOFCs, the Ni-YSZ support plays a key role in providing required electrical properties and robust mechanical behavior. In the present study, this well-established Ni-YSZ support is used to maintain the proton conducting fuel cell integrity. The cell is in a Ni-YSZ (375 μm support)/Ni-BZCYYb (20 μm anode functional layer)/BZCYYb (10 μm electrolyte)/LSCF-BZCYYb (25 μm cathode) configuration. Maximum power density values of 166, 218 and 285 mW/cm2 have been obtained at 600, 650 and 700°C, respectively. AC impedance spectroscopy results show values of 2.17, 1.23 and 0.76 Ω•cm2 at these temperatures where the main resistance contributor above 600°C is ohmic resistance. Very fine NiO and YSZ powders were used to achieve a suitable sintering shrinkage which can enhance the electrolyte sintering. During co-sintering of the support and BZCYYb electrolyte layers, the higher shrinkage of the support layer led to compressive stress in the electrolyte, thereby enhancing its densification. The promising results of the current study show that a new generation of proton conducting fuel cells based on the chemically and mechanically robust Ni-YSZ support can be developed which can improve long term performance and reduce fabrication costs of proton conducting fuel cells. This article is protected by copyright. All rights reserved.

An attempt has been made here to synthesize (1-x)Ba0.6Sr0.4CZY-xGDC (x = 0, 0.2, 0.5) composite electrolytes and investigated their phase(s), X-ray photo spectra (XPS) and conduction properties. All compositions possess dual phases (perovskite-type as well as cubic fluorite structure) and show proton conduction in various atmospheres. Homogeneous formation and compatibility between phases have been confirmed from X-ray diffraction analysis. Detailed X-ray photoelectron spectroscopy (XPS) studies on the oxidation states of barium, strontium, gadolinium, cerium, zirconium, yttrium and oxygen was performed. With increasing ‘x’, oxygen vacancy concentration increases as cerium ions in 4+ oxidation state decreases. The conduction behavior of composites depicts the protonic in nature and total activation energy lying in the range of 0.16-0.24 eV. This study indicates that the conductivity increases with GDC content in composite electrolytes and highest conductivity is found for composite with x = 0.5. These characteristics are useful to make (1-x)Ba0.6Sr0.4CZY-xGDC composite electrolytes as promising candidate of central membrane for advanced fuel cell technology. This article is protected by copyright. All rights reserved.

In order to investigate the effects of composite production and the role of the counter cation for metal phosphate conductors, changes in the solid-state nuclear magnetic resonance (NMR) spectra and magnetic relaxation times caused by the removal of volatile products and water washing were examined for various metal pyrophosphate (MP2 O7 -MO2 ; M = Sn, Si, Ti, and Zr). Acidic species could be detected by 1 H MAS NMR spectra for all the composites except ZrP2 O7 -ZrO2 that had the lowest conductivity. The 31 P DD-MAS NMR spectra for MP2 O7 -MO2 composites showed different signal patterns depending on the counter cations participating in the ion exchange as a result of different microstructures. Combinational analysis of 31 P DD-MAS and 31 P CP-MAS NMR spectra of the composites indicated that protonic bulk phosphates were observed at slightly lower fields than non-protonic bulk phosphates in all of the MP2 O7 -MO2 composites. After water washing, the acidic species and the protonic bulk phosphates of MP2 O7 -MO2 composites disappeared or were reduced to trace amounts. The T1 H values of the water-washed composites lengthened because of removal of orthophosphoric acid, although the T1 P values remained almost unchanged. The results of the solid-state NMR studies suggest that the protonic bulk phosphates of MP2 O7 -MO2 composites do not generally distribute in the bulk but exist in the interface between excess H3 PO4 and the bulk. Copyright © 2016 John Wiley & Sons, Ltd.

The solution-processed sodium-alginate (SA) films, with nanoporous/nanochannel microstructure, possess a total absorbed water number of 10420 ± 395 molecules per square nanometer, which gives rise to a high proton conductivity of 4.0 × 10−4 S cm−1. When SA films used as gate dielectric in the thin film transistors, electric-double-layer (EDL) would be formed whether at the dielectric/channel or at dielectric/gate electrode interface, leading to a huge specific capacitance and low operating voltage for the TFTs. More importantly, due to the three-dimensional proton conducting characteristic, one can design the TFT device structure expediently from conventional vertical gate coupling to laterally coplanar gate coupling structure. The TFTs with ease-design device layout have potential applications in multifunctional electronic devices.

To improve the high-temperature performance of proton exchange membranes, the polybenzimidazole (PBI)/α-zirconium phosphate (α-Zr(HPO4)2·nH2O, α-ZrP) proton exchange composite membranes were prepared in this study. PBI polymer containing a large amount of ether units has been synthesized from 3,3′- diaminobenzidine (DAB) and 4,4′-oxybis (benzoic acid) by a direct polycondensation in polyphosphoric acid. The polymer exhibited a good solubility in most polar solvents. Inorganic proton conductor α-ZrP nanoparticles have been obtained using a synthesis route involving separate nucleation and aging steps (SNAS). The effects of α-ZrP doping content on the composite membrane performance were investigated. It was found that the introduction of ZrP improved the thermal stability of the composite membranes. The PBI/ZrP composite membranes exhibited excellent mechanical strength. The composite membrane with 10 wt% ZrP showed the highest proton conductivity of 0.192 S cm−1 at 160°C under anhydrous condition. The proton conducting mechanism of the PBI/ZrP composite membranes was proposed to explain the proton transport phenomena. The experimental results suggested that the PBI/ZrP composite membranes may be a promising polymer electrolyte used in high temperature proton exchange membrane fuel cells (HT-PEMFCs) under anhydrous condition. POLYM. ENG. SCI., 56:622–628, 2016. © 2016 Society of Plastics Engineers

The primary issue of polymer electrolytes is to achieve high ion conductivity while retaining mechanical properties. A nanocomposite electrolyte with the inverse hexagonal cylindrical phase (three-dimensionally continuous domains for ion conduction and embedded domains for mechanical support) is prepared through the electrostatic self-assembly of a polyoxometalate (H3 PW12 O40 , PW) and a triblock copolymer poly(N-vinyl pyrrolidone)-block-polystyrene-block-poly(N-vinyl pyrrolidone) (PSP). The cylindrical nanocomposite exhibits a conductivity of 1.32 mS cm-1 and a storage modulus of 4.6 × 107 Pa at room temperature. These two values are higher than those of pristine PSP by two orders of magnitudes and a factor of six, respectively. PW clusters are used as multifunctional nano-additives (morphological inducer, proton conductor, and nano-enhancer) and their incorporation achieves the simultaneous improvement in both conductive and mechanical performance.

A proton conductor displaying high anhydrous proton conductivity (≈10(-2) S cm(-1)) and good performance over a broad temperature range is presented. This hybrid material is produced via doping HCl into open-framework chalcogenide(C2N2H10)(C2N2H9)2 Cu8 Sn3S12, and has cubopolyhedral cavities and multiple channels.

Kaolinite intercalated with 2-picolinic acid was prepared and characterized by scanning electron microscopy, powder X-ray diffraction, infrared spectroscopy, and thermogravimetric analysis. The proton conductivity (σ) of the material is 1.85 × 10–10 S cm–1 at 353 K and gradually increases to 1.7 × 10–7 S cm–1 at 393 K under N2 (anhydrous environment) with an activation energy of Ea = 1.93 eV, whereas σ = 1.56 × 10–7 S cm–1 under 80 % relative humidity at 353 K with Ea = 0.91 eV. The crystal structure optimized with the Cambridge Sequential Total Energy Package discloses the absence of a dense H-bond network in the layer space of kaolinite, which explains the low proton conductivity and high proton transfer activation energy of the intercalated proton conductor.

The cover picture shows the solid state battery where graphene oxide (GO) is used as proton conducting solid electrolyte. Respective discharge capacity and power density of the cell is found to be 360 μA h and 19.5 mW kg−1 at a constant current drain of 3 μA under experimental condition. GO based proton conductors as solid electrolyte are cleaner, cheaper and fascicle alternative for applications with low energy feedback. More information can be found in article number 1700054 by Yuta Shudo, Md. Saidul Islam, Mohammad Razaul Karim, Nurun Nahar Rabin, Kosuke Wakata, Ryo Ohtani, Masaaki Nakamura, Leonard F. Lindoy, and Shinya Hayami*.

The influence of indium doping on chemical stability, sinterability, and electrical properties of BaCe0.5Zr0.3Y0.2O3-δ was investigated. The phase purity and the chemical stability of the powders in humid pure CO2 were evaluated by XRD. The dense electrolyte pellets were formed after the calcination at 1450°C for 8 h. SEM images and shrinkage plot showed that the sinterability of the samples was apparently improved by doping indium. The electrical conductivity was measured by impedance test through two-point method, at both low (200–350°C) and high temperature ranges (450–850°C) in different atmospheres. BaCe0.4Zr0.3In0.1Y0.2O3-δ has been proved to be the optimal composition which simultaneously maximized the chemical stability, sinterability, and electrical conductivity which reached 1.1 × 10−2 S/cm in wet hydrogen at 700°C, comparing with the 1.3 × 10−2 S/cm for original BaCe0.5Zr0.3Y0.2O3-δ. Anode support fuel cell with a thin BaCe0.4Zr0.3In0.1Y0.2O3-δ electrolyte (15 μm) was fabricated by spin coating method. Maximum power density of 0.651 W/cm2 was obtained when operating at 700°C and fed by humid H2 (containing H2O 3 vol%). The obtained fuel cell could efficiently run at 650°C for more than 100 h without any attenuation.

Yttrium and indium co-doped barium zirconate is investigated to develop a chemically stable and sintering active proton conductor for solid oxide fuel cells (SOFCs). BaZr0.8Y0.2-xInxO3- δ possesses a pure cubic perovskite structure. The sintering activity of BaZr0.8Y0.2-xInxO3- δ increases significantly with In concentration. BaZr0.8Y0.15In0.05O3- δ (BZYI5) exhibits the highest total electrical conductivity among the sintered oxides. BZYI5 also retains high chemical stability against CO2, vapor, and reduction of H2. The good sintering activity, high conductivity, and chemical stability of BZYI5 facilitate the fabrication of durable SOFCs based on a highly conductive BZYI5 electrolyte film by cost-effective ceramic processes. Fully dense BZYI5 electrolyte film is successfully prepared on the anode substrate by a facile drop-coating technique followed by co-firing at 1400 °C for 5 h in air. The BZYI5 film exhibits one of the highest conductivity among the BaZrO3-based electrolyte films with various sintering aids. BZYI5-based single cells output very encouraging and by far the highest peak power density for BaZrO3-based proton-conducting SOFCs, reaching as high as 379 mW cm−2 at 700 °C. The results demonstrate that Y and In co-doping is an effective strategy for exploring sintering active and chemically stable BaZrO3-based proton conductors for high performance proton-conducting SOFCs.

The effects of doped low-valence cations on the properties of the SnP2O7 proton conductor at ambient temperature are investigated from changes in solid-state NMR spectra and nuclear magnetic relaxation times. Although the T1H values increased with decreasing acidity as a result of cation exchange, the 1H chemical shifts moved to lower field in Al- and In-doped materials compared with undoped ones. Furthermore, the shifts changed to higher field in Mg-doped materials, suggesting the existence of different protonic species in those materials. The bulk phosphate chemical shifts in the 31P dipolar-decoupling MAS NMR spectra were very similar, regardless of the nature and amount of the doping species. On the other hand, by 1H/31P cross-polarization MAS NMR, P2O7 signals interacting with an interstitial proton [Q1(proton)] were observed in all the undoped and doped SnP2O7, while acidic P–OH-type phosphate signals [Q1(acid)] were additionally observed in the Mg-doped conductor. The different affinity of the proton with the dopants and phosphates caused lower conductivity and larger activation energy in the Mg-doped materials, compared with those in the In- and Al-doped materials. Copyright © 2014 John Wiley & Sons, Ltd.

BaZr0.7Sn0.1Y0.2O3–δ (BZSY) is developed as a novel chemically stable proton conductor for solid oxide fuel cells (SOFCs). BZSY possesses the same cubic symmetry of space group Pm-3m with BaZr0.8Y0.2O3-δ (BZY). Thermogravimetric analysis (TGA) and X-ray photoelectron spectra (XPS) results reveal that BZSY exhibits remarkably enhanced hydration ability compared to BZY. Correspondingly, BZSY shows significantly improved electrical conductivity. The chemical stability test shows that BZSY is quite stable under atmospheres containing CO2 or H2O. Fully dense BZSY electrolyte films are successfully fabricated on NiO–BZSY anode substrates followed by co-firing at 1400 °C for 5 h and the film exhibits excellent electrical conductivity under fuel cell conditions. The single cell with a 12-μm-thick BZSY electrolyte film outputs by far the best performance for acceptor-doped BaZrO3-based SOFCs. With wet hydrogen (3% H2O) as the fuel and static air as the oxidant, the peak power density of the cell achieves as high as 360 mWcm−2 at 700 °C, an increase of 42% compared to the reported highest performance of BaZrO3-based cells. The encouraging results demonstrate that BZSY is a good candidate as the electrolyte material for next generation high performance proton-conducting SOFCs.

A simple chemical bath deposition is used to coat a complex porous ceramic scaffold with a conformal Ni layer. The resulting composite is used as a solid oxide fuel cell electrode, and its electrochemical response is measured in humidified hydrogen. X‐ray tomography is used to determine the microstructural characteristics of the uncoated and Ni‐coated porous structure, which include the surface area to total volume, the radial pore size, and the size of the necks between the pores.

Fuel cells with BaZr0.1Ce0.7Y0.2O3–δ (BZCY) proton-conducting electrolyte is fabricated using spray-modified pressing method. In the present study the spray-modified pressing technology is developed to prepare thin electrolyte layers on porous Ni-BZCY anode supports. SEM data show the BZCY electrolyte film is uniform and dense, well-bonded with the anode substrate. An anode-supported fuel cell with BZCY electrolyte and Ba0.5Sr0.5Co0.8Fe0.2O3–δ (BSCF) cathode is characterized from 600 to 700 °C using hydrogen as fuel and ambient air as oxidant. Maximum power density of 536 mW cm–2 along with a 1.01 V OCV at 700 °C is obtained. Impedance spectra show that Ohmic resistances contribute minor parts to the total ones, for instance, only ~23% when operating at 600 °C. The results demonstrate that spray-modified pressing technology offers a simple and effective way to fabricate quality electrolyte film suitable to operate in intermediate temperature.

The power generation properties of a novel dot matrix fuel cell using an inorganic micro-proton conductor were evaluated in dry gas mixtures of hydrogen and oxygen during room-temperature operation. The single dot matrix fuel cell was composed of aggregates of micro-electrolyte dots filling pores arranged in a matrix form on a Teflon or polyimide substrate with Pt/C and Pt catalytic electrodes. Micro-electrolyte dots were prepared by the sol–gel method using titanium phosphorus oxides as the proton conductive hybrid materials. The open-circuit voltage of the single cell became higher when using a small dot diameter and achieved a maximum of 500 mV with an electrolyte dot density of 17 dots/cm2 in the dry gas mixtures during room-temperature operation. This value corresponds to about one-half of the theoretical electromotive force. Moreover, the current density of the single cell increased with the dot diameter such that it grew to 8 mA/cm2 at a dot diameter of 500 µm. As a result, dot matrix fuel cells connected in series and parallel were found to achieve the cell performance of high-energy density such as used by high-energy microchips. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.

Fine particles of a solid proton conductor Sb0.2Sn0.8P2O7 were incorporated in PBI-H3PO4 membranes with 20 wt.%. In SEM figures, the Sb0.2Sn0.8P2O7 particles exhibited even and uniform distribution in the PBI-Sb0.2Sn0.8P2O7 membrane. Influences of the immersing time and the concentration of H3PO4 solution for immersion on H3PO4 loading level were investigated. H3PO4 loading level was found an important factor on membrane conductivity. Incorporation of Sb0.2Sn0.8P2O7 in the PBI-H3PO4 membrane resulted in greater membrane conductivities. In the single cell tests, the peak power density of the membrane electrode assembly (MEA) with the PBI-Sb0.2Sn0.8P2O7-H3PO4 membrane was also greater than that of a MEA with PBI-H3PO4 membrane. One MEA using PBI-Sb0.2Sn0.8P2O7-H3PO4 membrane achieved a peak power density of 0.67 W cm–2 at 175 °C with H2/O2 and exhibited satisfactory stability.

This paper reports on the one-pot synthesis and characterization of the functionalized mesoporous SBA-15 silica, which contains two loadings of the different acid groups [CO2H, PO(OH)2 and SO3H]. The thermodynamic features of the water that was confined in these porous silicas was investigated by Differential Scanning Calorimetry (DSC). The results showed that the melting behaviour of the confined water was mainly governed by the pore diameter and, as a consequence, indicated that the chemical “decoration” of the porous surface did not play a key role in the water thermodynamics. On the contrary, the proton conductivity of the hydrated mesoporous materials, which was examined under a wide range of temperatures (–100 to 70 °C), was strongly dependent on both the physical state of the confined water and the acidity of the functional groups that were located at the porous surface. The proton conductivity was shown to be directly related to the pKa and the density of the functional groups attached to the mesopore surface. The high conductivity values that were obtained at a low temperature when the confined water is frozen, led us to postulate that the SO3H-functionalized SBA-15 sample could be a promising candidate for electrolyte solid applications in fuel cells.

The high-pressure Raman studies of pure, Yb-modified, protonated and non-protonated SrZrO3 dense ceramics were performed between 0.1 and 40 GPa using a diamond anvil cell. Lanthanide-modified, protonated SrZrO3 perovskites are potential materials for electrolytic membrane in fuel cells and electrolysers working at medium temperature. The comparison of the Raman spectra shows important differences in the pressure behaviour between the pure and Yb-modified SrZrO3 ceramics. SrZrO3 exhibits a rigid structure without any structural modification, whereas for both SrZr0.93 Yb0.07 O2.965 and SrZr0.93 Yb0.07 O2.962 H0.003 a sequence of structural modifications at 10, 20 and 35 GPa is revealed. The character of these structural modifications is very similar to that observed as a function of the temperature (orthorhombic Pnma 750 °C pseudo-tetragonal Imma 840 °C tetragonal I4/mcm 1070 °C cubic Pm3m), which suggests that they can be considered as the phase transitions. Despite the low level of proton content (0.3% mole/mole), significant difference between protonated and non-protonated compounds is observed for the 700–750 cm−1 doublet assigned to the ZrO octahedron stretching mode, perturbed by an oxygen atom vacancy and/or neighbouring Yb ion. The location of proton is discussed. Copyright © 2011 John Wiley & Sons, Ltd.

The interface between mismatched perovskite oxides presents novel physical and chemical features of interest for the development of engineered materials with tailored properties. In this article, we report on the presence and properties of a regular network of misfit dislocations (MDs), which self-assembles at the interface between a thin film of the proton conductor BaZr 0.8 Y 0.2 O 2.9 and the substrate, the (110) oriented NdGaO 3 wide-gap insulator. The conductivity properties of this system strongly depend on the atmosphere at which a thermal annealing is carried out. Namely, a conductivity increase is observed after annealing at 450 °C in wet atmosphere. An annealing in dry environment at the same temperature brings back the conductivity to its pristine value. X-ray diffraction measurements show a strong increase of the strain field associated with the dislocation network, after annealing in wet atmosphere, suggesting that hydroxyl groups mostly accumulate in the cores of the interface MDs rather than in the bulk of the BaZr 0.8 Y 0.2 O 2.9 thin film. A further annealing in dry environment allows to recover the initial value of the strain field. The reported data indicate a strong involvement of the interface MDs in the transport properties of perovskite oxide interfaces.

Decreasing the dimensions of heterogeneous mixtures of ionic conductors towards the nanoscale results in ionic conduction enhancements, caused by the increased influence ofthe interfacial space-charge regions. For a composite of TiO 2 anatase and solid acid CsHSO 4 , the strong enhancement of the ionic conductivity at the nanoscale also can be assigned to this space-charge effect. Surprisingly high hydrogen concentrations in the order of 10 21 cm -3 in TiO 2 are measured, which means that about 10% of the available sites for H + ions are filled on average. Such high concentrations require a specific elaboration of the space-charge model that is explicitly performed here, by taking account of the large occupation numbers on the exhaustible sites. It is shown that ionic defects with negative formation enthalpy reach extremely high concentrations near the interfaces and throughout the material. By performing first-principles density functional theory calculations, it is found that proton insertion from CsHSO 4 into the TiO 2 particles is preferred compared to neutral hydrogen atom insertion and indeed that the formation enthalpy is negative. Moreover, the average proton fractions in Ti0 2 , estimated by the theoretical ionic density profiles, are in good agreement with the experimental observations.

The novel perfluorinated vinyl ether containing sulfonimide and phosphonic acid functionalities, CF^2=CFOCF^2CF(CF^3)-OCF^2CF^2SO^2NHSO^2(CF^2)^2P(O)(OH)^2, has been synthesized by multiple reaction steps. It is a very strong bi-functional acid and exhibits a high degree of stability in aqueous solution at an elevated temperature. These properties make it an attractive monomer for the preparation of the co-polymer with TFE to obtain the high quality ionomer membrane and proton conductor.

[EN] The electrochemical properties of mixed conducing ceramic¿ceramic composites for proton conducting fuel cells have been investigated. Different ratios of Pr0.58Sr0.4Fe0.8Co0.2O3¿¿¿BaCe0.9Yb0.1O3¿¿ composites have been tested as cathodes in symmetrical cells based on BaCe0.9Y0.1O3¿¿ dense electrolytes. Impedance measurements have been carried out in the temperature range of 600¿800¿°C under wet (2.5%) air. Different dilutions on both oxygen partial pressure and water content have been performed as a function of the temperature in order to characterise the processes (surface reaction and charge transport) occurring at the composite electrode under oxidising conditions. The variation of the impedance spectra after replacing protonated water by heavy water has been studied in order to understand the role of the proton transport in the overall composite cathode operation. Additional four-point DC-conductivity measurements have been done under different atmospheres comprising different oxygen partial pressures and H2O/D2O saturation for composites and single materials., Funding from Universitat Politècnica de València (grant FPI-UPV-2007-06), the Spanish Ministry for Science and Innovation (Project ENE-2008-06302) and European Union (FP7 Project EFFIPRO – grant Agreement 227560) are kindly acknowledged. Authors are indebted to S. Jiménez for sample preparation.

Poly(benzimidazole)s (PBIs) are a class of high-performance polymers which have been receiving increasing interest during the last years due to their high potential as constituents of membrane materials in proton-exchange membrane fuel cells (PEMFCs). In addition to the importance of PBI in fuel-cell technology, there are a number of other applications (e.g., catalysis) that make use of the special properties of this material. The scope of this Minireview is to first give a short overview about the use of nanostructured, mesoporous PBI as a proton conductor. Secondly, the use of spirobifluorene derivatives as new monomers, which allow the synthesis of hierarchically structured PBI, is presented. Limitations of traditional synthetic methods will be discussed, and an ionothermal scheme towards PBI will be presented as a versatile tool for the synthesis of plain and spirobifluorene-based PBIs. Finally, the use of electrospinning as a powerful processing technique for PBI will be presented briefly.

OH− and H3O+ species in hydrates and simple oxides are rather well characterised from their IR, Raman and inelastic neutron points of view. For the H+ (H2O) species in solid state the variability is well established and assignment remains discussed. The question of the vibrational signature of isolated proton (e.g. the ionic proton, a proton sharing its interaction with more than two acceptors) and its dynamic nature (proton gas, polaron,…) is open. H+-containing modified perovskites A(Ba,Sr,…) B(Zr,Ce,Ti,…) O3 are potential ceramic membranes for fuel cell and medium temperature water electrolysis (300–800 °C). Comparison studies of the protonated and non-protonated lanthanide/rare earth-modified perovskites of type Ba(Sr)Zr(Ti)O3 as well as Al-modified BaTiO3 show that a broad component centred at 2500 cm−1 is observed after ‘proton insertion’. Its intensity is correlated to the protonic species content as well as to the conductivity of the materials. The mixed nature of this feature is discussed: fluorescence related to the dangling bonds, A, B, C bands or new phenomena related to the ionic protons and associated electronic defect. Copyright © 2008 John Wiley & Sons, Ltd.

Sb-doped SnP2O7 were prepared and characterised with XRD, FTIR, SEM and EIS. The preparation parameters were optimised taking into consideration the influence of H3PO4 content in the reactants and PmOn impurities. Conductivities of SnP2O7 with different Sb doping levels were studied from 100 to 300 °C in un-humidified air. The conductivity of 20 mol-% Sb-doped SnP2O7 was greater than 0.1 S cm–1 at 300 °C. The effect of heat treatment was identified as an important factor in the preparation of the proton conductors. The time dependence of the conductivity demonstrated Sb-doped SnP2O7 as a promising intermediate temperature solid proton conductor.

The performance characteristics of fuel cells based on proton conducting BaCeO3 solid electrolyte doubly doped with gadolinium and praseodymium are reported. The amount of praseodymium doping is systematically varied in order to optimize the fuel cell performance. Fuel cells incorporating the optimum amount of praseodymium exhibit power density levels enhanced by a factor of three, compared to those incorporating undoped BaCeO3. The performance of the fuel cell is essentially the same irrespective of the fuel used. However, the performance of the fuel cell is slightly better in hydrogen than in ammonia. Nevertheless, fuel cells operated in ammonia show a greater decrease in peak power density with decreasing temperature than those operated in hydrogen. This behaviour suggests that alternative anode materials need to be utilized at lower operating temperatures.

Low operating voltages for p-channel organic field-effect transistors (OFETs) can be achieved by using an electrolyte as the gate insulator. However, mobile anions in the electrolyte can lead to un ...

Polysiloxane phosphonic acid doped polybenzimidazole (PBI) high-temperature membranes were fabricated in this study. Polysiloxane phosphonic acid instead of phosphoric acid was used as a proton conductor to prevent acid from leaking. The membrane samples with different amounts of PBI were prepared and characterized with respect to the structure, thermal properties, oxidative stability, proton conductivity, and mechanical properties. The Fourier transform infrared results show that hydrogen bonds formed between PBI and polysiloxane phosphonic acid. Thermal analysis confirmed that the temperature at which membrane experienced 10% weight loss was above 230°C. None of the membrane samples broke into pieces after Fenton reagent testing. The proton conductivity of the membrane samples with 5% PBI was up to 0.034 S/cm at 140°C under nominally anhydrous conditions. The tensile strength of the membrane samples with 10% PBI was 18.3 MPa. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42956.

A composite membrane of sulfonated poly(ether sulfone) (SPES)/poly(ether sulfone) (PES) nanofiber (NF) mat impregnated with Nafion was prepared and evaluated for its potential use as a proton conductor for proton exchange membrane (PEM) fuel cells. The supporting composite nanofibrous mat was prepared by solution blowing of a mixture of SPES/PES solution. The characteristics of the SPES/PES NF and the composite membrane, such as morphology, thermal stability, and performance of membrane as PEMs, were investigated. The performance of composite membranes was compared with that of Nafion117. The introduction of solution blown NFs to composite membranes modestly improved proton conductivity, water swelling, and methanol permeability. Therefore, composite membrane containing SPES/PES NFs can be considered as a novel PEM for fuel cell applications. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42572.

An organic–inorganic proton conductive composite material consisting of a biopolymer was prepared by mixing the pectin, tetraethyl titanate, and imidazole. Although the pectin material without the composite dissolved in water, the pectin–inorganic composite material did not show water solubility. In addition, in the composite material, the pectin and imidazole formed an acid–base structure by an electrostatic interaction, and as a result, these composite materials showed a thermal stability at intermediate temperatures (100–200°C). Furthermore, these composite materials indicated the proton conductivity of 5.6 × 10−4 S cm−1 at 180°C under anhydrous conditions. The activation energy of the proton conduction under anhydrous conditions was 0.32–0.22 eV and these values were one order of magnitude higher than that of the typical humidified perfluorinated membrane, such as Nafion®. The organic–inorganic composite material consisting of a biocomponent may have the potential to be utilized as a novel proton conductor under anhydrous conditions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42433.