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  • Journal article
    Kucernak A, Malko D, Lopes T, 2016,

    Performance of Fe-N/C oxygen reduction electrocatalysts towards NO−₂, NO, and NH₂OH electroreduction from fundamental insights into the active center to a new method for environmental nitrite destruction

    , Journal of the American Chemical Society, Vol: 138, Pages: 16056-16068, ISSN: 1520-5126

    Although major progress has recently been achieved through ex situ methods, there is still a lack of understanding of the behavior of the active center in non-precious metal Fe–N/C catalysts under operating conditions. Utilizing nitrite, nitric oxide, and hydroxylamine as molecular probes, we show that the active site for the oxygen reduction reaction (ORR) is different under acidic and alkaline conditions. An in-depth investigation of the ORR in acid reveals a behavior which is similar to that of iron macrocyclic complexes and suggests a contribution of the metal center in the catalytic cycle. We also show that this catalyst is highly active toward nitrite and nitric oxide electroreduction under various pH values with ammonia as a significant byproduct. This study offers fundamental insight into the chemical behavior of the active site and demonstrates a possible use of these materials for nitrite and nitric oxide sensing applications or environmental nitrite destruction.

  • Journal article
    Kucernak ARJ, kakati, Fahy KF, 2016,

    Using corrosion-like processes to remove poisons from electrocatalysts: a viable strategy to chemically regenerate irreversibly poisoned polymer electrolyte fuel cells

    , Electrochimica Acta, Vol: 222, Pages: 888-897, ISSN: 1873-3859

    Poisoning of Pt/C catalysts due to SO2 on a rotating disk electrode (RDE), and as part of the cathode layer in a single cell fuel cell and fuel cell stack are studied in terms of the system performance, and the effect of electrochemical and chemical post treatment to remove the adsorbed sulphur containing species. It is found that external polarisation can only recover the ORR performance of catalyst on an RDE after SO2 poisoning when an applied potential of 1.6 V(RHE) is used for 1 ks. An alternative approach is to use ozone, as in the presence of this species, the electrode potential is raised to ~1.6V(RHE) due to the high potential of the ozone reduction reaction. The high open circuit potential leads to a mixed potential and was found also to be highly efficient at removing the poison via coupled ozone reduction and poison oxidation. The ozone process is found to work efficiently at the catalyst level as shown through rotating disk electrode studies and also in single cell fuel cells. Furthermore we demonstrate for the first time the recovery of a SO2 poisoned fuel cell stack using the mixed-potential approach and ozone as a reactant. The cleaning process is fast (~10 minutes), occurs at room temperature, and does not require any special modification to the fuel cell. The process may be applicable to a wide range of poisons which can be oxidatively removed from platinum at high potentials.

  • Journal article
    Chakrabarti BK, Nir DP, Yufit V, Tariq F, Rubio Garcia J, Maher R, Kucernak A, Aravind PV, Brandon NPet al., 2016,

    Studies of performance enhancement of rGO-modified carbon electrodes for Vanadium Redox Flow Systems

    , ChemElectroChem, Vol: 4, Pages: 194-200, ISSN: 2196-0216

    Reduced graphene oxide (rGO) suspended in an N,N′-dimethylformamide (DMF) solvent underwent electrophoretic deposition (EPD) on carbon paper (CP) electrodes. X-ray computed micro-tomography (XMT) indicates a 24 % increase in the specific surface area of CP modified with rGO in comparison to the untreated sample. Furthermore, XMT confirms that the deposition also penetrates into the substrate. Raman analysis shows that the rGO deposited is more amorphous than the CP electrode. A significant reduction in charge-transfer resistance of the VO2+/VO2+ reaction is also observed (from impedance measurements) in modified samples in comparison to untreated CP electrodes.

  • Journal article
    Malko D, Kucernak A, Lopes T, 2016,

    In-situ electrochemical quantification of active sites in Fe-N/C non-precious metal catalysts

    , Nature Communications, Vol: 7, Pages: 1-7, ISSN: 2041-1723

    The economic viability of low temperature fuel cells as clean energy devices is enhanced by the development of inexpensive oxygen reduction reaction catalysts. Heat treated iron and nitrogen containing carbon based materials (Fe–N/C) have shown potential to replace expensive precious metals. Although significant improvements have recently been made, their activity and durability is still unsatisfactory. The further development and a rational design of these materials has stalled due to the lack of an in situ methodology to easily probe and quantify the active site. Here we demonstrate a protocol that allows the quantification of active centres, which operate under acidic conditions, by means of nitrite adsorption followed by reductive stripping, and show direct correlation to the catalytic activity. The method is demonstrated for two differently prepared materials. This approach may allow researchers to easily assess the active site density and turnover frequency of Fe–N/C catalysts.

  • Journal article
    Lopes T, Kucernak A, Malko D, Ticianelli EAet al., 2016,

    Mechanistic Insights into the Oxygen Reduction Reactionon Metal–N–C Electrocatalysts under Fuel Cell Conditions

    , ChemElectroChem, Vol: 3, Pages: 1580-1590, ISSN: 2196-0216

    Three different transition metal-C-N catalysts are tested under a range of fuel cell conditions. It is found that common features of the polarisation curve can be explained by a change in electrocatalytic mechanism. Utilising a simple model to quantify the change in mechanisms, iR free results of the fuel cell experiments are fit and found to be represented by a common set of parameters. The change in mechanism is assumed to be a switch from four electron reduction of oxygen to water to a two electron reduction to hydrogen peroxide followed by disproportionation of the hydrogen peroxide to water and oxygen. The data is used to estimate a mass specific exchange current density towards the ORR in the range 10-11-10-13 A g-1 depending on the catalyst. For the reduction of oxygen to hydrogen peroxide, the mass specific exchange current density is estimated to be in the range 10-2-10-3 A g-1. Utilising the electrokinetic model, it is shown how the mass transport losses can be extracted from the polarisation curve. For all three catalyst layers studied, these mass transport losses reach about 100mV at a current density of 1 A cm-2. Finally a discussion of the performance and site density requirements of the non-precious metal catalysts are provided, and it is estimated that the activity towards the ORR needs to be increased by an order of magnitude, and the site density by two/three orders of magnitude in order to compete with platinum as an ORR electrocatalyst.

  • Journal article
    Malko D, lopes T, Ticianelli E, Kucernak Aet al., 2016,

    A catalyst layer optimisation approach using electrochemical impedance spectroscopy for PEM fuel cells operated with pyrolysed transition metal-N-C catalysts

    , Journal of Power Sources, Vol: 323, Pages: 189-200, ISSN: 0378-7753

    The effect of the ionomer to carbon (I/C) ratio on the performance of single cell polymer electrolyte fuel cells is investigated for three different types of non-precious metal cathodic catalysts. Polarisation curves as well as impedance spectra are recorded at different potentials in the presence of argon or oxygen at the cathode and hydrogen at the anode. It is found that a optimised ionomer content is a key factor for improving the performance of the catalyst. Non-optimal ionomer loading can be assessed by two different factors from the impedance spectra. Hence this observation could be used as a diagnostic element to determine the ideal ionomer content and distribution in newly developed catalyst-electrodes. An electrode morphology based on the presence of inhomogeneous resistance distribution within the porous structure is suggested to explain the observed phenomena. The back-pressure and relative humidity effect on this feature is also investigated and supports the above hypothesis. We give a simple flowchart to aid optimisation of electrodes with the minimum number of trials.

  • Journal article
    Kucernak ARJ, Zalitis CM, 2016,

    General Models for the Electrochemical Hydrogen Oxidation and Hydrogen Evolution Reactions – Theoretical Derivation and Experimental Results Under Near Mass-Transport Free Conditions

    , Journal of Physical Chemistry C, Vol: 120, Pages: 10721-10745, ISSN: 1932-7455

    Full derivations of Heyrovsky-Volmer (HV), Tafel-Volmer(TV), Heyrovsky-Tafel(HT), and Heyrovsky-Tafel-Volmer(HTV) mechanisms under steady state conditions are provided utilising a new theoretical framework which allows better understanding of the each of the mechanistic currents and part currents. Simple and easily implemented equations are presented, which provide both the hydrogen coverage and electrochemical current as a function of overpotential and relevant kinetic parameters. It is shown how these responses are governed by a set of dimensionless parameters associated with the ratio of electrokinetic parameters. For each of the different mechanisms, an “atlas” of Hads coverage with overpotential and corresponding current density is provided, allowing an understanding of all possible responses depending on the dimensionless parameters. Analysis of these mechanisms provides the limiting reaction orders of the exchange current density for protons and bimolecular hydrogen for each of the different mechanisms, as well as the possible Tafel slopes as a function of the molecular symmetry factor, . Only the HV mechanism is influenced by pH whereas the TV,HT, and HTV mechanisms are not. The cases where the equations simplify to limiting forms are discussed. Analysis of the exchange current density from experimental data is discussed, and it is shown that fitting the linear region around the equilibrium potential underestimates the true exchange current density for all of the mechanisms studied. Furthermore, estimates of exchange current density via back-extrapolation from large overpotentials is also shown to be highly inaccurate. Analysis of Tafel slopes is discussed along with the mechanistic information which can and cannot be determined. The new models are used to simultaneously fit sixteen experimental responses of Pt/C electrodes in acid towards the her/hor as a function of , pH, p(H2), and temperature, using a consistent set of electrokinetic parame

  • Conference paper
    Beruski O, Lopes T, Kucernak A, Perez Jet al., 2016,

    Comparison between Darcy's law and Darcy-Brinkman formulation for reactant transport in PEFC porous media

    , Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
  • Journal article
    Kucernak ARJ, kakati, Unnikrishnan A, Rajalakshmi N, Jafri R, Dhathathreyan Ket al., 2016,

    Recovery of Polymer Electrolyte Fuel Cell exposed to sulfur dioxide

    , International Journal of Hydrogen Energy, Vol: 41, Pages: 5598-5604, ISSN: 1879-3487

    Sulfur dioxide (SO2) is a common atmospheric contaminant which has a deleterious effect on fuel cells. The performance of a Polymer Electrolyte Fuel Cell (PEFC) utilising a Pt on nitrogen doped graphene support as the cathode catalyst was studied in the presence of air contaminated with known levels of SO2. The nitrogen doped graphene supported platinum was synthesized by a hydrothermal method. At levels of 25ppm SO2 in air there was within 15 minutes a 28 % reduction in the PEFC performance at 0.5 V. The performance degradation was more severe at higher SO2 concentrations. At 100 ppm SO2 in air the performance degraded by 91% at the same potential. The power loss of the fuel cell could not be recovered by externally polarising the PEFC at 1.6 V. Even after continuous potential cycling of the cell for 9 h only 80% of the initial performance could be recovered. However, a 15 minute treatment with 0.4% O3 in air showed almost a 100% performance recovery of the 100ppm SO2 contaminated fuel cell. The enhanced recovery of the fuel cell is related both to the chemical reaction of O3 with the adsorbed sulphur contaminant, and an increase of cathode potential during the electrochemical treatment.

  • Journal article
    Edel JB, Kornyshev AA, Kucernak AR, Urbakh Met al., 2016,

    Fundamentals and applications of self-assembled plasmonic nanoparticles at interfaces

    , Chemical Society Reviews, Vol: 45, Pages: 1581-1596, ISSN: 1460-4744

    This tutorial review will introduce and explore fundamental and applied aspects of using electrolytic interfaces incorporating nanoscale building blocks for use in novel applications such as sensors, and tunable optics. In order to do this, it is important to be able to understand the principles behind even the simplest of immiscible interfaces such as that of the Liquid | Liquid and Solid | Liquid Qualitatively, the picture is simple however the complexity is easily compounded by the addition of electrolyte, and further compounded by addition of more complex entities such as nanoparticles. Nevertheless combining all these components surprisingly results in an elegant solution, where the nanoparticles have the ability to self assemble at the interface with a high level of control. Importantly, this opens up the door to development of new types of materials with a range of applications which have only recently been exploited. As such initially we begin with a description of the fundamentals related to liquid | Liquid and Solid | Liquid interfaces both with and without electrolyte. The discussions then shifts to a description of biasing the interface by application of an electric field. This is followed by an exploration of nanoparticle assembly and disassembly at the interface by controlling parameters such as ligand composition, charge, pH, and electric field. Finally a description of the state-of-the-art is given in terms of current applications and possible future directions. It is perhaps fair to say that these new frontiers have caused great excitement within the sensing community not only due to the simplicity of the technique but also due to the unprecedented levels of sensitivity

  • Journal article
    Malko D, Lopes T, Symianakis E, Kucernak ARJet al., 2016,

    The intriguing poison tolerance of non-precious metal oxygen reduction reaction (ORR) catalysts

    , Journal of Materials Chemistry A, Vol: 4, Pages: 142-152, ISSN: 2050-7496

    Electrochemical devices such as fuel cells are key to a sustainable energy future. However the applicability of such underrealistic conditions is not viable to date. Expensive precious metals are used as electrocatalysts and contaminants presentin the operating media poison the utilized catalysts. Here the one pot synthesis of a highly active, self-supporting andsurprisingly poison tolerant catalyst is reported. The polymerisation of 1,5-Diaminonaphthalene provides self-assemblednanospheres, which upon pyrolysis form a catalytically active high surface area material. Tolerance to a wide range ofsubstances that poison precious metal based catalysts combined with high electrocatalytic activity might enable numerousadditional technological applications. In addition to fuel cells these could be metal-air batteries, oxygen-depolarized chloralkalicathodes, oxygen sensors, medical implantable devices, waste water treatment and as counter electrodes for manyother sensors where the operating medium is a complex and challenging mixture.

  • Journal article
    Kucernak ARJ, Fahy KF, Naranammalpuram Sundaram VN, 2015,

    Facile synthesis of palladium phosphide electrocatalysts and their activity for the hydrogen oxidation, hydrogen evolutions, oxygen reduction and formic acid oxidation reactions

    , Catalysis Today, Vol: 262, Pages: 48-56, ISSN: 1873-4308

    We demonstrate a new approach for producing highly dispersed supported metal phosphide powders with small particle size, improved stability and increased electrocatalytic activity towards some useful reactions. The approach involves a one-step conversion of metal supported on high surface area carbon to the metal phosphide utilising a very simple and scalable synthetic process. We use this approach to produce PdP₂ and Pd₅P₂ particles dispersed on carbon with a particle size of 4.5–5.5 nm by converting a commercially available Pd/C powder. The metal phosphide catalysts were tested for the oxygen reduction, hydrogen oxidation and evolution, and formic acid oxidation reactions. Compared to the unconverted Pd/C material, we find that alloying the P at different levels shifts oxide formation on the Pd to higher potentials, leading to greater stability during cycling studies (20% more ECSA retained, 5k cycles) and in thermal treatment under air. Hydrogen absorption within the PdP₂ and Pd₅P₂ particles is enhanced. The phosphides compare favourably to the most active catalysts reported to date for formic acid oxidation, especially PdP₂, and there is a significant decrease in poisoning of the surface compared to Pd alone. The mechanistic changes in the reactions studied are rationalised in terms of increased water activation on the surface phosphorus atoms of the catalyst. One of the catalysts, PdP₂/C is tested in a fuel cell as anode and cathode catalyst and shows good performance.

  • Journal article
    Markiewicz M, Zalitis C, Kucernak A, 2015,

    Performance measurements and modelling of the ORR on fuel cell electrocatalysts - the modified double trap model

    , Electrochimica Acta, Vol: 179, Pages: 126-136, ISSN: 1873-3859

    Experimental results for the ORR (oxygen reduction reaction) in perchloric acid for ultra low loading Pt/Celectrodes have been fitted to a number of different ORR mechanisms. These were accomplished as afunction of temperature (280–330 K), oxygen partial pressure(0:01 < po2p0o2< 1) and potential (0.3–1.0V vs.RHE). A reaction exponent for oxygen of 1 0.1 across the potential range 0.3–0.85V vs. RHE is confirmed.From the experimental results it is clear that the surface becomes increasingly blocked towards the ORRas overpotential increases (i.e. as the potential decreases from 0.6 to 0.3 V vs. RHE). The double trap model[J.X. Wang, J. Zhang, R.R. Adzic, J. Phys. Chem. A, 111 (2007) 12,702] fails to account for this observation,although we have produced a modified version to include the formation of OOHad intermediates. Theseintermediates block the electrode at larger overpotentials and lead to a decrease in electrocatalystperformance compared to a Tafel type approximation. Furthermore these intermediates can lead to theformation of hydrogen peroxide at large overpotentials, an experimental observation which is currentlypoorly described by models.The decreased activity at large overpotentials suggests that blocking of active catalyst sites may be asimportant to catalyst activity in an operating fuel cell as the absolute performance of the electrode in thelow overpotential region as typically measured on an RDE. It may also offer an explanation to theincreased losses seen in fuel cell electrodes at lower catalyst loadings – i.e. the loses, which are typicallyascribed to increased mass transport loses, may instead result from decreased electrocatalyticperformance at high overpotentials.

  • Journal article
    Ahmad EA, Tileli V, Kramer D, Mallia G, Stoerzinger KA, Shao-Horn Y, Kucernak AR, Harrison NMet al., 2015,

    Optimizing Oxygen Reduction Catalyst Morphologies from First Principles

    , Journal of Physical Chemistry C, Vol: 119, Pages: 16804-16810, ISSN: 1932-7455

    Catalytic activity of perovskites for oxygen reduction (ORR) wasrecently correlated with bulk d-electron occupancy of the transition metal. Weexpand on the resultant model, which successfully reproduces the high activity ofLaMnO3 relative to other perovskites, by addressing catalyst surface morphology asan important aspect of the optimal ORR catalyst. The nature of reaction sites onlow index surfaces of orthorhombic (Pnma) LaMnO3 is established from FirstPrinciples. The adsorption of O2 is markedly influenced by local geometry andstrong electron correlation. Only one of the six reactions sites that result from experimentally confirmed symmetry-breakingJahn−Teller distortions is found to bind O2 with an intermediate binding energy while facilitating the formation of superoxide, animportant ORR intermediate in alkaline media. As demonstrated here for LaMnO3, rational design of the catalyst morphology topromote specific active sites is a highly effective optimization strategy for advanced functional ORR catalysts.

  • Journal article
    Kucernak ARJ, zalitis C, Sharman J, Wright Eet al., 2015,

    Properties of the hydrogen oxidation reaction on Pt/C catalysts at optimised high mass transport conditions and its relevance to the anode reaction in PEFCs and cathode reactions in electrolysers

    , Electrochimica Acta, Vol: 176, Pages: 763-776, ISSN: 1873-3859

    Using a high mass transport floating electrode technique with an ultra-low catalyst loading (0.84-3.5 gPt cm-2) of commonly used Pt/C catalyst (HiSPEC 9100, Johnson Matthey), features in the hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) were resolved and defined, which have rarely been previously observed. These features include fine structure in the hydrogen adsorption region between 0.18 < V vs. RHE < 0.36 V vs. RHE consisting of two peaks, an asymptotic decrease at potentials greater than 0.36 V vs. RHE, and a hysteresis above 0.1 V vs. RHE which corresponded to a decrease in the cathodic scan current by up to 50 % of the anodic scan. These features are examined as a function of hydrogen and proton concentration, anion type and concentration, potential scan limit, and temperature. We provide an analytical solution to the Heyrovsky-Volmer equation and use it to analyse our results. Using this model we are able to extract catalytic properties (without mass transport corrections; a possible source of error) by simultaneously fitting the model to HOR curves in a variety of conditions including temperature, hydrogen partial pressure and anion/H+ concentration. Using our model we are able to rationalise the pH and hydrogen concentration dependence of the hydrogen reaction. This model may be useful in application to fuel cell and electrolyser simulation studies.

  • Patent
    edel, turek, cecchini, Kornyshev, Paget, kucernaket al., 2015,


    The invention relates to a method of detecting the presence of an analyte associated with a nanoparticle layer formed at a liquid-liquid interface. The method comprises removing a portion of one of the liquid phases; and detecting the presence of the analyte by Raman spectroscopy, Infra Red spectroscopy and/or fluorescence spectroscopy. The invention further relates to a kit for use in the method, comprising a sample vessel for receiving in use, a first and second liquid phase; wherein said phases are immiscible and wherein one or both of the first or the second liquid phase comprise nanoparticles, and instructions to allow analysis of an analyte in a sample according to the claimed method

  • Patent
    Kucernak ARJ, edel, turek, cecchini, pagetet al., 2015,


    , EP2880425
  • Journal article
    Kucernak ARJ, 2015,

    Electrochemical Characterization and Quantified Surface Termination Obtained by LEIS and XPS of Orthorhombic and Rhombohedral LaMnO<sub>3</sub> Powders

    , Journal of Physical Chemistry C, Vol: 119, Pages: 12209-12217, ISSN: 1932-7455

    LaMnO3 powder synthesized by glycine combustion synthesis with the rhombohedral and orthorhombic structures has been characterized by the combination of low energy ion scattering (LEIS) and X-ray photoelectron spectroscopy (XPS), while the electrocatalytic activity for the oxygen reduction reaction is measured with the rotating disk electrode (RDE) method. Quantification of the surface terminations obtained by LEIS suggests that the orthorhombic LaMnO3 crystallites are near thermodynamic equilibrium as surface atomic ratios compare well with those of equilibrium morphologies computed by a Wulff construction based on computed surface energies. Both rhombohedral and orthorhombic structures present the same La/Mn atomic ratio on the surface. Electrochemical activity of the two structures is found to be the same within the error bar of our measurements. This result is in disagreement with results previously reported on the activity of the two structures obtained by the coprecipitation method [Suntivich et al. Nat. Chem. 2011, 3 (7), 546], and it indicates that the preparation method and the resulting surface termination might play a crucial role for the activity of perovskite catalysts.

  • Patent
    Kucernak ARJ, malko, lopes, 2015,


    , WO2015049318

    The present invention relates to a method for preparing a catalyst which can be used to catalyse the oxygen reduction reaction (ORR). The invention also provides a catalyst obtained from the method and its use as an electrode, for example, in a galvanic cell, an electrolytic cell or an oxygen sensor.

  • Patent
    Kucernak ARJ, 2015,

    Fuel Cell

    A fuel cell assembly is disclosed comprising a fuel cell electrode component and a reactant gas flow component ink bonded thereto. In one aspect direct bonding of a gas diffusion layer with a flow field is achieved allowing a simplified structural configuration. In another aspect improved component printing techniques reduce corrosion effects. In a further aspect flow fields are described providing reactant channels extending in both the horizontal and vertical directions, i.e. providing three dimensional flow. In a further aspect an improved wicking material allows wicking away and reactant humidification. In a further aspect improved mechanical fastenings and connectors are provided. In a further aspect improved humidification approaches are described. Further improved aspects are additionally disclosed.

  • Journal article
    Stockford C, Brandon N, Irvine J, Mays T, Metcalfe I, Book D, Ekins P, Kucernak A, Molkov V, Steinberger-Wilckens R, Shah N, Dodds P, Dueso C, Samsatli S, Thompson Cet al., 2015,

    H2FC SUPERGEN: An overview of the Hydrogen and Fuel Cell research across the UK

    , International Journal of Hydrogen Energy, Vol: 40, Pages: 5534-5543, ISSN: 1879-3487

    The United Kingdom has a vast scientific base across the entire Hydrogen and Fuel Cell research landscape, with a world class academic community coupled with significant industrial activity from both UK-based Hydrogen and Fuel Cell companies and global companies with a strong presence within the country. The Hydrogen and Fuel Cell (H2FC) SUPERGEN Hub, funded by the Engineering and Physical Sciences Research Council (EPSRC), was established in 2012 as a five-year programme to bring the UK's H2FC research community together. Here we present the UK's current Hydrogen and Fuel Cell activities along with the role of the H2FC SUPERGEN Hub.

  • Conference paper
    Kalyvas C, Mason T, Gibbs C, Brett D, Kucernak Aet al., 2015,

    The Flexi Planar Fuel Cell

    , University of Sheffield Engineering Symposium, Publisher: USES
  • Journal article
    Lopes T, Ho M, Kakati BK, Kucernak ARJet al., 2015,

    Assessing the performance of reactant transport layers and flow fields towards oxygen transport: A new imaging method based on chemiluminescence

    , JOURNAL OF POWER SOURCES, Vol: 274, Pages: 382-392, ISSN: 0378-7753
  • Conference paper
    Greenhalgh ES, Shirshova N, Kucernak A, Shaffer MSP, Teixeira R, Bismarck A, Kireitseu M, Shelton Ret al., 2015,


    , 20th International Conference on Composite Materials (ICCM), Publisher: AALBORG UNIV PRESS
  • Journal article
    Shirshova N, Qian H, Houlle M, Steinke JHG, Kucernak ARJ, Fontana QPV, Greenhalgh ES, Bismarck A, Shaffer MSPet al., 2014,

    Multifunctional structural energy storage composite supercapacitors

    , Faraday Discussions, Vol: 172, Pages: 81-103, ISSN: 1359-6640

    This paper addresses the challenge of producing multifunctional composites that can simultaneously carry mechanical loads whilst storing (and delivering) electrical energy. The embodiment is a structural supercapacitor built around laminated structural carbon fibre (CF) fabrics. Each cell consists of two modified structural CF fabric electrodes, separated by a structural glass fibre fabric or polymer membrane, infused with a multifunctional polymeric electrolyte. Rather than using conventional activated carbon fibres, structural carbon fibres were treated to produce a mechanically robust, high surface area material, using a variety of methods, including direct etching, carbon nanotube sizing, and carbon nanotube in situ growth. One of the most promising approaches is to integrate a porous bicontinuous monolithic carbon aerogel (CAG) throughout the matrix. This nanostructured matrix both provides a dramatic increase in active surface area of the electrodes, and has the potential to address mechanical issues associated with matrix-dominated failures. The effect of the initial reaction mixture composition is assessed for both the CAG modified carbon fibre electrodes and resulting devices. A low temperature CAG modification of carbon fibres was evaluated using poly(3,4-ethylenedioxythiophene) (PEDOT) to enhance the electrochemical performance. For the multifunctional structural electrolyte, simple crosslinked gels have been replaced with bicontinuous structural epoxy–ionic liquid hybrids that offer a much better balance between the conflicting demands of rigidity and molecular motion. The formation of both aerogel precursors and the multifunctional electrolyte are described, including the influence of key components, and the defining characteristics of the products. Working structural supercapacitor composite prototypes have been produced and characterised electrochemically. The effect of introducing the necessary multifunctional resin on the mechanical properties

  • Journal article
    Iden H, Kucernak AR, 2014,

    Analysis of effective surface area for electrochemical reaction derived from mass transport property

    , JOURNAL OF ELECTROANALYTICAL CHEMISTRY, Vol: 734, Pages: 61-69, ISSN: 1572-6657
  • Patent
    kucernak, 2014,

    fuel cell

    A fuel cell assembly is disclosed comprising a fuel cell electrode component and a reactant gas flow component ink bonded thereto. In one aspect direct bonding of a gas diffusion layer with a flow field is achieved allowing a simplified structural configuration. In another aspect improved component printing techniques reduce corrosion effects. In a further aspect flow fields are described providing reactant channels extending in both the horizontal and vertical directions, i.e. providing three dimensional flow. In a further aspect an improved wicking material allows wicking away and reactant humidification. In a further aspect improved mechanical fastenings and connectors are provided. In a further aspect improved humidification approaches are described. Further improved aspects are additionally disclosed.

  • Journal article
    Obeisun OA, Meyer Q, Robinson J, Gibbs CW, Kucernak AR, Shearing PR, Brett DJLet al., 2014,

    Development of open-cathode polymer electrolyte fuel cells using printed circuit board flow-field plates: Flow geometry characterisation

    , INTERNATIONAL JOURNAL OF HYDROGEN ENERGY, Vol: 39, Pages: 18326-18336, ISSN: 0360-3199
  • Journal article
    Greenhalgh ES, Ankersen J, Asp LE, Bismarck A, Fontana QPV, Houlle M, Kalinka G, Kucernak A, Mistry M, Nguyen S, Qian H, Shaffer MSP, Shirshova N, Steinke JHG, Wienrich Met al., 2014,

    Mechanical, electrical and microstructural characterisation of multifunctional structural power composites

    , Journal of Composite Materials, Vol: 49, Pages: 1823-1834, ISSN: 1530-793X
  • Journal article
    Kucernak ARJ, Sundaram VNN, 2014,

    Nickel phosphide: the effect of phosphorus content on hydrogen evolution activity and corrosion resistance in acidic medium

    , Journal of Materials Chemistry A, Vol: 2, Pages: 17435-17445, ISSN: 2050-7496

    Transition metal phosphides possess novel, structural, physical and chemical properties and are an emerging new class of materials for various catalytic applications. Electroplated or electrolessly plated nickel phosphide alloy materials with achievable phosphorus contents <15 at% P are known to be more corrosion resistant than nickel alone, and have been investigated as hydrogen evolution catalysts in alkaline environments. However, there is significant interest in developing new inexpensive catalysts for solid polymer electrolyte electrolysers which require acid stable catalysts. In this paper, we show that by increasing the phosphorus content beyond the limit available using electroplating techniques (∼12 at% P), the nickel based phosphides Ni12P5 and Ni2P with higher levels of phosphorus (29 and 33 at% P) may be utilised for the hydrogen evolution reaction (HER) in acidic medium. Corrosion resistance in acid is directly correlated with phosphorus content – those materials with higher phosphorus content are more corrosion resistant. Hydrogen evolution activity in acid is also correlated with phosphorus content – Ni2P based catalysts appear to be more active for the hydrogen evolution reaction than Ni12P5. Electrochemical kinetic studies of the HER reveal high exchange current densities and little deviation in the Tafel slope especially in the lower overpotential regime for these nickel phosphide catalysts. The electrochemical impedance spectroscopy response of the respective system in acidic medium reveals the presence of two time constants associated with the HER.

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