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  • Journal article
    Parra-Puerto A, Ng KL, Fahy K, Goode AE, Ryan MP, Kucernak Aet al., 2019,

    Supported transition metal phosphides: Activity survey for HER, ORR, OER and corrosion resistance in acid and alkaline electrolytes

    , ACS Catalysis, Vol: 9, Pages: 11515-11529, ISSN: 2155-5435

    Carbon supported MxPy (M = Ni, Co, W, Cr and Mo) were prepared via pyrolysis using a very simple and scalable method utilizing non-toxic metal and phosphorous precursors. The electrochemical hydrogen evolution (HER), oxygen reduction (ORR), and oxygen evolution (OER) reactions and corrosion resistance under both acid and alkaline conditions were examined for all these catalysts and compared to the benchmark catalysts Pt/C (HER/ORR) and IrO2(OER). The highest activities were found in alkaline solutions for Co2P for HER and ORR and Ni2P for OER. Good activity for these was also found in acid for some of these reactions, although the catalysts suffered from susceptibility to corrosion. Co2P was further studied in an alkaline environment as it shows high catalytic activity towards the oxygen reduction reaction (ORR) without significant hysteresis. The onset potential (at 0.5 mA cm-2) obtained was 0.8 V and a Tafel slope value of 38 mV dec-1 with a maximum kinetic mass activity of 2870 A gCo-1 at 0.7 V (RHE). Utilising high resolution transmission electron microscopy (HRTEM) it is possible to observe high-surface area needle-like single crystal cobalt oxide structures on the surfaces of the Co2P particles at the beginning of the ORR. Hence the high rates of initial corrosion of the Co2P identified appear to be associated with the dissolution and precipitation of Cobalt oxide on the particle surface. The as-synthesised Co2P/C also shows good performance in an 8-hour stability test for the Oxygen Evolution Reaction (OER), carried out at 1.6 V vs. RHE in alkaline conditions, with negligible drop in current density over time. Interestingly, in an acidic environment the catalyst is very active towards 2-electron- oxygen reduction leading to H2O2 with high selectivity (85%). It is intriguing that the pH dependence on this catalyst towards the ORR is similar to that seen for gold.

  • Journal article
    Ma Y, Sikdar D, Fedosyuk A, Velleman L, Klemme DJ, Oh S-H, Kucernak ARJ, Kornyshev AA, Edel JBet al., 2019,

    Electrotunable nanoplasmonics for amplified surface enhanced Raman spectroscopy

    , ACS Nano, ISSN: 1936-0851

    Tuning the properties of optical metamaterials in real time is one of the grand challenges of photonics. Being able to do so will enable a new class of photonic materials for use in applications such as surface enhanced Raman spectroscopy and reflectors/absorbers. One strategy to achieving this goal is based on the electrovariable self-assembly and disassembly of two-dimensional nanoparticle arrays at a metal liquid interface. As expected the structure results in plasmonic coupling between NPs in the array but perhaps as importantly between the array and the metal surface. In such a system the density of the nanoparticle array can be controlled by the variation of electrode potential. Due to the additive effect, we show that less than 1 V variation of electrode potential can give rise to a dramatic simultaneous change in optical reflectivity from ~93 % to ~1 % and the amplification of the SERS signal by up to 5 orders of magnitude. The process allows for reversible tunability. These concepts are demonstrated in this manuscript, using a platform based on the voltage-controlled assembly of 40 nm Au-nanoparticle arrays at a TiN/Ag electrode in contact with an aqueous electrolyte. We show that all the physics underpinning the behaviour of this platform works precisely as suggested by the proposed theory, setting the electrochemical nanoplasmonics as a promising new direction in photonics research.

  • Journal article
    Tariq F, Rubio-Garcia J, Yufit V, Bertei A, Chakrabarti BK, Kucernak A, Brandon Net al., 2018,

    Uncovering the mechanisms of electrolyte permeation in porous electrodes for redox flow batteries through real time in situ 3D imaging

    , SUSTAINABLE ENERGY & FUELS, Vol: 2, Pages: 2068-2080, ISSN: 2398-4902
  • Journal article
    Rubio-Garcia J, Kucernak ARJ, Charleson A, 2018,

    Direct visualization of reactant transport in forced convection electrochemical cells and its application to Redox Flow Batteries

    , Electrochemistry Communications, Vol: 93, Pages: 128-132, ISSN: 1388-2481

    A novel, simple and low cost electrochemiluminescence imaging method for monitoring mass transport phenomena in a redox flow battery-like system is presented. Luminol solutions were pumped through a flow field (FF) with a given design. At the flowfield/electrode interface light is emitted upon dye oxidation allowing direct visualization of channels, U-bends and regions of poor wetting. Image analysis allows direct visualization of reactant distribution and poor mass transport through tortuous materials. These results were compared with the experimental performance of an all‑vanadium redox flow battery with different FFs as a function of flow and good correlation achieved.

  • Journal article
    Jackson C, Smith GT, Markiewicz M, Inwood DW, Leach AS, Whalley PS, Kucernak AR, Russell AE, Kramer D, Levecque PBJet al., 2018,

    Support induced charge transfer effects on electrochemical characteristics of Pt nanoparticle electrocatalysts

    , Journal of Electroanalytical Chemistry, Vol: 819, Pages: 163-170, ISSN: 1572-6657

    The electrokinetic properties of Pt nanoparticles supported on Carbon (Pt/C) and Boron Carbide-Graphite composite (Pt/BC) are compared over a wide potential range. The influence of the support on the electronic state of Pt was investigated via in-situ X-ray Absorption Spectroscopy. Pt d-band filling, determined from XANES white line analysis, was lower and nearly constant between 0.4 and 0.95V vs. RHE for Pt/BC, indicating more positively charged particles in the double layer region and a delay in the onset of oxide formation by about 0.2V compared to the Pt/C catalyst, which showed a marked increase in d-band vacancies above 0.8V vs. RHE. Moreover, δμ analysis of the XANES data indicated a lack of sub-surface oxygen for the Pt/BC catalyst compared to the Pt/C catalyst above 0.9V vs. RHE. Additional anion adsorption on the Pt/BC in the double layer region, detected by CO displacement, was also confirmed by XANES analysis of the d-band occupancy. The H 2 oxidation activities of electrodes with low catalyst loadings were assessed under high mass transport conditions using the floating electrode methodology. The metal-support interaction between the Pt and BC support improved the maximum hydrogen oxidation current density by 1.4 times when compared to Pt/C.

  • Journal article
    Montelongo Y, Sikdar D, Ma Y, McIntosh AJS, Velleman L, Kucernak AR, Edel JB, Kornyshev AAet al., 2017,

    Electrotunable nanoplasmonic liquid mirror.

    , Nature materials, Vol: 16, Pages: 1127-1135, ISSN: 1476-1122

    Recently, there has been a drive to design and develop fully tunable metamaterials for applications ranging from new classes of sensors to superlenses among others. Although advances have been made, tuning and modulating the optical properties in real time remains a challenge. We report on the first realization of a reversible electrotunable liquid mirror based on voltage-controlled self-assembly/disassembly of 16 nm plasmonic nanoparticles at the interface between two immiscible electrolyte solutions. We show that optical properties such as reflectivity and spectral position of the absorption band can be varied in situ within ±0.5 V. This observed effect is in excellent agreement with theoretical calculations corresponding to the change in average interparticle spacing. This electrochemical fully tunable nanoplasmonic platform can be switched from a highly reflective 'mirror' to a transmissive 'window' and back again. This study opens a route towards realization of such platforms in future micro/nanoscale electrochemical cells, enabling the creation of tunable plasmonic metamaterials.

  • Journal article
    Velleman L, Sikdar D, Turek V, Kucernak A, Roser SJ, Kornyshev AA, Edel JBet al., 2016,

    Tuneable 2D self-assembly of plasmonic nanoparticles at liquid | liquid interfaces

    , Nanoscale, Vol: 8, Pages: 19229-19241, ISSN: 2040-3372

    Understanding the structure and assembly of nanoparticles at liquid | liquid interfaces is paramount to their integration into devices for sensing, catalysis, electronics and optics. However, many difficulties arise when attempting to resolve the structure of such interfacial assemblies. In this article we use a combination of X-ray diffraction and optical reflectance to determine the structural arrangement and plasmon coupling between 12.8 nm diameter gold nanoparticles assembled at a water | 1,2-dichloroethane interface. The liquid | liquid interface provides a molecularly flat and defect-correcting platform for nanoparticles to self-assemble. The amount of nanoparticles assembling at the interface can be controlled via the concentration of electrolyte within either the aqueous or organic phase. At higher electrolyte concentration more nanoparticles can settle at the liquid | liquid interface resulting in a decrease in nanoparticle spacing as observed from X-ray diffraction experiments. The coupling of plasmons between the nanoparticles as they come closer together is observed by a red-shift in the optical reflectance spectra. The optical reflectance and the X-ray diffraction data are combined to introduce a new ‘plasmon ruler’. This allows extraction of structural information from simple optical spectroscopy techniques, with important implications in understanding the structure of nanoparticle films at liquid interfaces and their self-assembly.

  • 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
    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
    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.

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

    METHOD OF DETECTING AN ANALYTE IN A SAMPLE USING RAMAN SPECTROSCOPY, INFRA RED SPECTROSCOPY AND/OR FLUORESCENCE SPECTROSCOPY

    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.

  • 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 C, Stockford C, Brandon N, Irvine J, Mays T, Metcalfe I, Book D, Ekins P, Kucernak A, Molkou 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
    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
    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
  • 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
    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
  • Journal article
    Shirshova N, Qian H, Shaffer MSP, Steinke JHG, Greenhalgh ES, Curtis PT, Kucernak A, Bismarck Aet al., 2013,

    Structural composite supercapacitors

    , Composites Part A: Applied Science and Manufacturing, Vol: 46, Pages: 96-107, ISSN: 1359-835X

    This paper presents the development of multifunctional materials that perform a structural role whilst simultaneously storing electrical energy as a supercapacitor. Two structural carbon fibre woven electrodeswere separated by a woven glass fibre layer, and infused with a multifunctional polymer electrolyte. Following characterisation of electrochemical and compressive performance, working structural supercapacitor prototypes were demonstrated. Since the relative mechanical and electrical demands are application specific, an optimisation methodology is proposed. Multifunctional composites were achieved, which had compressive moduli of up to 39 GPa and capacitances of up to 52 mF g 1.

  • Journal article
    Ahmad EA, Mallia G, Kramer D, Tileli V, Kucernak AR, Harrison NMet al., 2012,

    Comment on "2D Atomic Mapping of Oxidation States in Transition Metal Oxides by Scanning Transmission Electron Microscopy and Electron Energy-Loss Spectroscopy"

    , PHYSICAL REVIEW LETTERS, Vol: 108, ISSN: 0031-9007
  • Journal article
    Turek V, Cecchini MP, Paget J, Kucernak AR, Kornyshev AA, Edel JBet al., 2012,

    A Plasmonic Ruler at the Liquid-Liquid Interface

    , ACS Nano
  • Journal article
    Ahmad EA, Liborio L, Kramer D, Mallia G, Kucernak AR, Harrison NMet al., 2011,

    Thermodynamic stability of LaMnO3 and its competing oxides: A hybrid density functional study of an alkaline fuel cell catalyst

    , PHYSICAL REVIEW B, Vol: 84, ISSN: 2469-9950
  • Conference paper
    Elias S, Quinson J, Britovsek GJP, Kucernak ARJet al., 2011,

    Electrocatalytic CO2 reduction using modified electrodes

    , 242nd National Meeting of the American-Chemical-Society (ACS), Publisher: AMER CHEMICAL SOC, ISSN: 0065-7727
  • Journal article
    Brett DJL, Kucernak AR, Aguiar P, Atkins SC, Brandon NP, Clague R, Cohen LF, Hinds G, Kalyvas C, Offer GJ, Ladewig B, Maher R, Marquis A, Shearing P, Vasileiadis N, Vesovic Vet al., 2010,

    What happens inside a fuel cell? Developing an experimental functional map of fuel cell performance

    , ChemPhysChem, Vol: 11, Pages: 2714-2731
  • Journal article
    Kucernak ARJ, Offer GJ, 2008,

    Calculating the coverage of saturated and sub-saturated layers of carbon monoxide adsorbed onto platinum

    , Journal of Electroanalytical Chemistry
  • Journal article
    Kucernak AR, Offer GJ, 2008,

    The role of adsorbed hydroxyl species in the electrocatalytic carbon monoxide oxidation reaction on platinum

    , PHYSICAL CHEMISTRY CHEMICAL PHYSICS, Vol: 10, Pages: 3699-3711, ISSN: 1463-9076
  • Journal article
    Vasileiadis N, Brett DJL, Vesovic V, Kucernak AR, Fontes E, Brandon NPet al., 2007,

    Numerical Modeling of a Single Channel Polymer Electrolyte Fuel Cell

    , J. Fuel Cell Sci. Tech., Vol: 4, Pages: 336-344
  • Journal article
    Brett DJL, Atkins S, Brandon NP, Vasileiadis N, Vesovic V, Kucernak ARet al., 2007,

    membrane resistance and current distribution measurements under various operating conditions in a polymer electrolyte fuel cell

    , Journal of Power Sources, Vol: 172, Pages: 2-13
  • Conference paper
    Brett DJL, Atkins S, Brandon NP, Vesovic V, Vasileiadis N, Kucernak Aet al., 2005,

    Localised electrochemical impedance measurements on a single channel of a solid polymer fuel cell

    , 3rd Symposium on Proton Conducting Membrane Fuel Cells, Publisher: ELECTROCHEMICAL SOCIETY INC, Pages: 336-348

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