A5074226300- Advancements in Solid Oxide Fuel Cells
- Electrocatalysts for Energy Conversion
- Fuel Cells and Related Materials
- Electrochemical Analysis and Applications
- Advanced battery technologies research
- Advancements in Battery Materials
- Conducting polymers and applications
- Advanced Battery Technologies Research
- Electronic and Structural Properties of Oxides
- Advanced Battery Materials and Technologies
- Multimedia Communication and Technology
- CO2 Reduction Techniques and Catalysts
- Magnetic and transport properties of perovskites and related materials
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Service-Oriented Architecture and Web Services
- Electrochemical sensors and biosensors
- ICT Impact and Policies
- Supercapacitor Materials and Fabrication
- Perovskite Materials and Applications
- Molecular Junctions and Nanostructures
- Peer-to-Peer Network Technologies
- Caching and Content Delivery
- Organic Electronics and Photovoltaics
- Catalytic Processes in Materials Science
Technical University of Denmark
2015-2025
Dublin City University
2000-2020
IRD Fuel Cells (Denmark)
2010-2018
Centre for Sustainable Energy
2011
Ericsson (Sweden)
1999-2010
University of Groningen
2008
University of Copenhagen
2006
Ørsted (Denmark)
2006
University of Hull
2005
Uppsala University
1997-2005
Electrochemical properties of Li+ ion insertion in nanoporous TiO2 (anatase) electrodes were studied by voltammetry. Linear and cyclic potential scans recorded as a function electrolyte concentration, film thickness, temperature. The currents directly proportional to the inner electrode area electrodes. reduction Ti4+ oxidation Ti3+ are sluggish follows irreversible kinetics. standard rate constant was (3.5 ± 0.5) × 10-10 cm/s. transfer coefficient close 0.5, indicating that drop appears...
Electrochemical insertion of lithium in nanoporous and CVD samples TiO2 (anatase) was studied by chronoamperometry. The currents following cathodic anodic potential steps were monitored as a function film thickness, temperature, electrolyte concentration. time dependence the generally exhibit behavior diffusion-limited process. It is demonstrated that magnitude scales directly with inner area electrodes. on rate extraction indicates reduction Ti4+ oxidation Ti3+ kinetically hindered....
Lithium-O2 (Li-O2) batteries are currently limited by a large charge overpotential at practically relevant current densities, and the origin of this has been heavily debated in literature. This paper presents series electrochemical impedance measurements suggesting that increase potential is not caused an internal resistance. It proposed shift instead dictated mixed parasitic reactions Li2O2 oxidation. The also confirm rapid loss near end discharge ("sudden death") explained transport...
Redox-active organic molecules are promising charge-storage materials for redox-flow batteries (RFBs), but material crossover between the posolyte and negolyte chemical degradation limiting factors in performance of all-organic RFBs. We demonstrate that bipolar electrochemistry 1,2,4-benzotriazin-4-yl (Blatter) radicals allows construction with symmetrical electrolyte composition. Cyclic voltammetry shows these also retain reversible presence water. The redox potentials derivatives a...
Electron microscopy characterization across the cathode–electrolyte interface of two different types intermediate temperature solid oxide fuel cells (IT‐SOFC) is performed to understand origin cell performance disparity. One IT‐SOFC had a sprayed‐cosintered Ce 0.90 Gd 0.01 O 1.95 (CGO10) barrier layer, other layer deposited by pulsed laser deposition (PLD) CGO10. Scanning electron microscopy, transmission (TEM), and backscattered diffraction (EBSD) investigations conclude that major source...
Sulfur impurities in carbon containing fuels for solid oxide fuel cells (SOFC), e.g. natural gas and biogas, typically lead to significant losses performance due the sulfur sensitivity of Ni/yttria-stabilized-zirconia (YSZ) anodes SOFC. Full having Ni/YSZ have been characterized during long-term galvanostatic operation internal reforming mixture (CH4/H2O/H2:30/60/10), with 2 ppm H2S exposure anode 500 hours at 850°C, different current densities. This work focus on effect over a few hundreds...
Carbon black (CB) additives commonly used to increase the electrical conductivity of electrodes in Li-ion batteries are generally believed be electrochemically inert cathodes. Decomposition electrolyte surface region CB cells at high voltages up 4.9 V is here studied using electrochemical measurements as well structural and characterizations. LiPF6 LiClO4 dissolved ethylene carbonate:diethylene carbonate (1:1) were study irreversible charge capacity cathodes when cycled between 2.5 V....
Symmetric aqueous organic redox flow batteries (RFBs) are potentially an inexpensive, durable, and safe energy storage technology. Unlike normal asymmetric batteries, they based on electrolytes that exist in at least three oxidation states can undergo a minimum of two distinct processes. We compute the potentials selected electrolytes, with intent to understand how interaction between units affects potentials. find electronic intramolecular hydrogen bonding be exploited tune difference...
Abstract While anion exchange membrane (AEM) water electrolysis has many advantages, its commercialization is impeded by the low alkaline stability of most AEM, due to fragility quaternary ammonium groups. Ion solvating membranes (ISM) can be an alternative, but so far require high concentrations. Here, it shown that sulfonation polybenzimidazole results in ISM which swell strongly 1 m KOH. Crosslinking with dibromoxylene controls swelling, and after activation conductivities >100 mS cm...
Abstract Ion conducting membranes play a crucial role in redox flow batteries, separating anolyte and catholyte while allowing proton transport to complete the circuit. However, most are trapped trade‐off relation show either low conductivity or high vanadium crossover. This study investigates use of dense sulfonated para ‐polybenzimidazole for batteries (VRFBs), analyzes effects membrane preparation process, thickness operating temperature on VRFB performance. The results demonstrate...
Common half-cell measurements deliver oxygen reduction activities linked to the chosen scan rate, limiting their value for fundamental and comparative studies on platinum. Here we show a deconvolution of intrinsic kinetics from effect surface We find an electronic oxygen, substantiate Tafel slope ~120 mV/decade, obtain exchange current density 13 ± 4 µA/cm2, activity 7 mA/cm2 at 900 mV. Eventually, broaden scope this analysis effects rearrangement, alloying, supported Pt nanoparticles,...
The electropolymerization of a series Ru and Os bis-terpyridine complexes that form rodlike polymers with bithienyl, quaterthienyl, or hexathienyl bridges has been studied. Absorption spectroscopy, scanning electron microscopy, cyclic voltammetry have used to characterize the monomers resulting polymer films. absolute dc conductivity quaterthienyl-bridged {Ru(tpy)2} {Os(tpy)2} is unusually large independent identity metal center at 1.6 x 10(-3) S cm(-1). maximum occurs formal potential each...
Molecular redox levels can be used to modulate tunneling currents through single or small numbers of molecules and induce molecular electronic device function. While most these devices require cryogenic conditions, room temperature operation has been demonstrated by using electrochemical gating in aqueous environments. The latter have, however, serious shortcomings with a view on their relatively high volatility narrow stability ranges terms potential. Here we report the first-time use an...
Abstract In recent years extended focus has been placed on monitoring and understanding degradation mechanisms in both solid oxide fuel cells electrolysis cells. The time-consuming nature of experiments the disparate conclusions from experiment reproductions indicates that not all are fully understood. Traditionally, cell attributed to materials, processing operating conditions. More recently, effect raw material gas impurities their long-term degradation. Minor have found play a significant...
Abstract Metal‐supported solid oxide fuel cells are expected to offer several potential advantages over conventional anode (Ni‐YSZ) supported cells. For example, increased resistance against mechanical and thermal stresses a reduction in material costs. When Ni‐YSZ based anodes used metal SOFC, elements from the active layer may inter‐diffuse with metallic support during sintering. This work illustrates how inter‐diffusion problem can be circumvented by using an alternative design on porous...
In this work we study the structural degradation of a laboratory Li-ion battery LiFePO4/Carbon Black (LFP/CB) cathode by various electron microscopy techniques including low kV Focused Ion Beam (FIB)/Scanning Electron Microscopy (SEM) 3D tomography. Several changes are observed in FIB/SEM images fresh and degraded cathodes, cracks LFP particles, secondary disconnected agglomeration CB. Low voltage (1 kV) SEM show that CB agglomerates have different brightness than CB, due to charging...
In this work an Equivalent Circuit Model (ECM) is developed and used to model impedance spectra measured on a commercial 26650 LiFePO4/Graphite cylindrical cell. The ECM based measurements modeling of recorded separately cathode (LiFePO4) anode (Graphite) samples, harvested from the Modeling single-electrode provided information about electronic ionic resistance in porous composite electrodes, as well solid state diffusion. Focused Ion Beam (FIB)/Scanning Electron Microscopy (SEM) samples...