A5013111265- Advancements in Battery Materials
- Nanoporous metals and alloys
- Advanced Battery Materials and Technologies
- Electrocatalysts for Energy Conversion
- Anodic Oxide Films and Nanostructures
- Supercapacitor Materials and Fabrication
- Advanced Battery Technologies Research
- Semiconductor materials and devices
- Electrochemical Analysis and Applications
- Extraction and Separation Processes
- Fuel Cells and Related Materials
- Molecular Junctions and Nanostructures
- Advanced battery technologies research
- Nanocluster Synthesis and Applications
- Semiconductor materials and interfaces
- Advanced Sensor and Energy Harvesting Materials
- Conducting polymers and applications
- Electrodeposition and Electroless Coatings
- Adhesion, Friction, and Surface Interactions
- Ferroelectric and Piezoelectric Materials
- Surface Modification and Superhydrophobicity
- Magnetic properties of thin films
- Advanced Materials and Mechanics
- Magnetic Properties and Applications
- MXene and MAX Phase Materials
Karlsruhe Institute of Technology
2014-2025
Applied Materials (Germany)
2025
Helmholtz-Institute Ulm
2013-2020
Applied Materials (United Kingdom)
2020
Universität Ulm
1996-2020
Center for NanoScience
2002-2009
Saarland University
2004-2008
FZI Research Center for Information Technology
2003-2007
Institute for Energetics and Interphases
2007
FIZ Karlsruhe – Leibniz Institute for Information Infrastructure
2003
Dimension changes on the order of 0.1% or above in response to an applied voltage have been reported for many types materials, including ceramics, polymers, and carbon nanostructures, but not, so far, metals. We show that reversible strain amplitudes comparable those commercial piezoceramics can be induced metals by introducing a continuous network nanometer-sized pores with high surface area controlling electronic charge density through potential relative electrolyte impregnating pores.
We report a macroscopic shrinkage by up to 30 vol % during electrochemical dealloying of Ag-Au. Since the original crystal lattice is maintained process, we suggest that formation nanoporous gold in our experiments accompanied creation large number defects and local plastic deformation.
We report the preparation of composite foils consisting two layers, one solid gold and nanoporous gold. Tip displacements several millimeters are observed when immersed in aqueous electrolytes electrochemical potential varied. This suggests that metals could be used as active component actors, it demonstrates for first time changes surface stress f metal−electrolyte interface can induce a macroscopic strain, orders magnitude larger than amplitudes which reached conventional cantilever...
The mechanical properties of nanoporous Au have been investigated by uniaxial compression. Micron-sized columns were machined in the surface using a focused Ga+ beam and compressed with flat punch nanoindenter. Using scaling laws for foams, yield strength 15nm diameter ligaments is estimated to be 1.5GPa, close theoretical Au. This value agrees well extrapolations submicron, fully dense gold shows that addition foam density structure, absolute size cell walls can used tailor properties.
Nanoporous gold, prepared by electrochemical dissolution of Ag from commercial white gold leaf, was investigated HAADF-STEM tomography. The three-dimensional reconstruction shows a fully connected network structure composed single-crystalline ligaments and pores. We have applied stereological analyses to characterize the pore volume fraction, specific surface area, mean curvature. exhibits broad distributions in as well ligament size, convex significant microstructural anisotropy. contain...
Lithium-ion battery electrodes contain a substantial amount of electrochemically inactive materials, including binders, conductive agents, and current collectors. These extra components significantly dilute the specific capacity whole thus have led to efforts utilize foils, for example, Al, as sole anode material. Interestingly, literature has many reports fast degradation Al electrodes, where less than dozen cycles can be achieved. However, in some studies, anodes demonstrate stable cycling...
Abstract The anode/electrolyte interface behavior, and by extension, the overall cell performance of sodium‐ion batteries is determined a complex interaction processes that occur at all components electrochemical across wide range size‐ timescales. Single‐scale studies may provide incomplete insights, as they cannot capture full picture this intertwined behavior. Broad, multiscale are essential to elucidate these processes. Within perspectives article, several analytical theoretical...
Sodium-ion batteries may develop into a cost-efficient alternative to lithium-ion batteries. Na3V2(PO4)3/C (NVP/C) is known be suitable electrode material for such that can used as an anode or cathode. Here, NVP/C-based electrodes were investigated in different cell configurations. The cycled against the materials hard carbon, Sb/C, SnSb/C, and sodium metal. Furthermore, NVP versus was investigated. When NVP/C other materials, cells exhibit relatively poor reliability, but NVP–NVP cells,...
The structural, electronic and magnetic properties of 4 nm metallic FePt particles were studied by X-ray diffraction (XRD), Rutherford backscattering spectroscopy (RBS), transmission electron microscopy (TEM), photo (XPS), magnetometry M\"ossbauer spectroscopy. At low temperatures, the data reveal an unusually high well defined hyperfine field compared to multilayer or bulk samples. anisotropy as-prepared embedded in a layer oleic acid molecules arises from surface contributions....
Attempts to use aluminum-based anodes in lithium-ion batteries often fail due fast capacity fading. Generally, this has been attributed pulverization of the electrode and large volume changes associated with phase transformation between crystalline α β phases Li-Al alloys. In study, these transformations were investigated aluminum films that lithiated either electrochemically or via direct reaction lithium metal. Scanning electron microscopy was used image samples at different stages...
Gold sponges consisting of bicontinuous, 3D networks branched nanowires and tortuous pores are prepared by anodic dissolution silver from Ag75Au25 alloy sheets in 1 mol L-1 HClO4, an electrochemical process occurring under mixed charge transfer mass transport control. Samples resulting characterized SEM, which reveals different surface bulk morphologies, EIS that allows estimate the Au sponge area through measurement its double layer capacity. This capacity depends linearly on attains values...
Nanoporous composites with nanoporous Pt matrix (see figure, coarsened structure) and micron-scale dendritic solid solution embeddings were fabricated by dealloying of Pt-Ag alloys. The combination large surface area nano-porosity dramatically enhanced compression strength dimensional stability (compared the conventional monolithic metals), allows this material for applications as sensors, actuators or catalysts.
We report a cantilever bending investigation into the variation of surface stress, f, with charge density, q, for (111)-textured thin films gold in aqueous NaF and HClO4. The graphs f(q) are highly linear, stress-charge coefficients, df/dq, −1.95 V 7 mM −2.0 10 HClO4 near potential zero charge. These values exceed some previously published experimental data by factor 2, but they agree recent ab initio calculations response vacuum.