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  • 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

  • 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

  • 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.

  • 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.

  • 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
  • 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
  • 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.

  • Journal article
    Varcoe JR, Atanassov P, Dekel DR, Herring AM, Hickner MA, Kohl PA, Kucernak AR, Mustain WE, Nijmeijer K, Scott K, Xu T, Zhuang Let al., 2014,

    Anion-exchange membranes in electrochemical energy systems

    , Energy & Environmental Science, Vol: 7, Pages: 3135-3191, ISSN: 1754-5706

    This article provides an up-to-date perspective on the use of anion-exchange membranes in fuel cells, electrolysers, redox flow batteries, reverse electrodialysis cells, and bioelectrochemical systems (e.g. microbial fuel cells). The aim is to highlight key concepts, misconceptions, the current state-of-the-art, technological and scientific limitations, and the future challenges (research priorities) related to the use of anion-exchange membranes in these energy technologies. All the references that the authors deemed relevant, and were available on the web by the manuscript submission date (30th April 2014), are included.

  • Journal article
    Smith G, Zalitis CM, Kucernak ARJ, 2014,

    Thin solid state reference electrodes for use in solid polymer electrolytes

    , ELECTROCHEMISTRY COMMUNICATIONS, Vol: 43, Pages: 43-46, ISSN: 1388-2481
  • Journal article
    Kalyvas C, Kucernak A, Brett D, Hinds G, Atkins S, Brandon Net al., 2014,

    Spatially resolved diagnostic methods for polymer electrolyte fuel cells: a review

  • Journal article
    Kakati BK, Kucernak ARJ, 2014,

    Gas phase recovery of hydrogen sulfide contaminated polymer electrolyte membrane fuel cells

    , JOURNAL OF POWER SOURCES, Vol: 252, Pages: 317-326, ISSN: 0378-7753
  • Journal article
    Daniels FA, Attingre C, Kucernak AR, Brett DJLet al., 2014,

    Current collector design for closed-plenum polymer electrolyte membrane fuel cells

    , JOURNAL OF POWER SOURCES, Vol: 249, Pages: 247-262, ISSN: 0378-7753
  • 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
  • Journal article
    Turek VA, Elliott LN, Tyler AII, Demetriadou A, Paget J, Cecchini MP, Kucernak AR, Kornyshev AA, Edel JBet al., 2013,

    Self-Assembly and Applications of Ultra-Concentrated Nanoparticle Solutions

    , ACS Nano
  • Conference paper
    Thepkaew J, Therdthianwong S, Therdthianwong A, Kucernak A, Wongyao Net al., 2013,

    Promotional roles of Ru and Sn in mesoporous PtRu and PtRuSn catalysts toward ethanol electrooxidation

    , 3rd International Conference of Fuel Cell & Hydrogen Technology (ICFCHT), Publisher: PERGAMON-ELSEVIER SCIENCE LTD, Pages: 9454-9463, ISSN: 0360-3199
  • Journal article
    Qian H, Kucernak AR, Greenhalgh ES, Bismarck A, Shaffer MSPet al., 2013,

    Multifunctional Structural Supercapacitor Composites Based on Carbon Aerogel Modified High Performance Carbon Fiber Fabric

    , ACS APPLIED MATERIALS & INTERFACES, Vol: 5, Pages: 6113-6122, ISSN: 1944-8244
  • Journal article
    Cousens NEA, Kucernak AR, 2013,

    Electrochemistry of the ionic liquid vertical bar oil interface: A new water-free interface between two immiscible electrolyte solutions

    , ELECTROCHEMISTRY COMMUNICATIONS, Vol: 31, Pages: 63-66, ISSN: 1388-2481
  • Conference paper
    Zalitis CM, Kramer D, Sharman J, Wright E, Kucernak ARet al., 2013,

    Pt Nano-Particle Performance for PEFC Reactions At Low Catalyst Loading and High Reactant Mass Transport

    , 13th Polymer Electrolyte Fuel Cell Symposium (PEFC), Publisher: ELECTROCHEMICAL SOC INC, Pages: 39-47, ISSN: 1938-5862
  • Journal article
    Ahmad EA, Mallia G, Kramer D, Kucernak AR, Harrison NMet al., 2013,

    The stability of LaMnO3 surfaces: a hybrid exchange density functional theory study of an alkaline fuel cell catalyst

    , JOURNAL OF MATERIALS CHEMISTRY A, Vol: 1, Pages: 11152-11162, ISSN: 2050-7488
  • Journal article
    Shirshova N, Bismarck A, Carreyette S, Fontana QPV, Greenhalgh ES, Jacobsson P, Johansson P, Marczewski MJ, Kalinka G, Kucernak ARJ, Scheers J, Shaffer MSP, Steinke JHG, Wienrich Met al., 2013,

    Structural supercapacitor electrolytes based on bicontinuous ionic liquid-epoxy resin systems

    , JOURNAL OF MATERIALS CHEMISTRY A, Vol: 1, Pages: 15300-15309, ISSN: 2050-7488

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