In situ redox cycle of a nickel-YSZ fuel cell anode in an environmental transmission electron microscope

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We present a theory stating how to overcome the classical Rayleigh-resolution limit. It is based upon a new resolution criterion in phase of coherent imaging process and its spatial resolution is thought to be only SNR limited. Recently, the experimental observation of systematically occurring phase singularities in coherent imaging of sub-Rayleigh distanced objects has been reported.1 The phase resolution criterion relies on the unique occurrence of phase singularities. A priori, coherent imaging system's

Due to their high specific energy and energy density, micro-solid oxide fuel cells1,2 (µ-SOFCs) are seen as one of the technologies that could help satisfying the continuously increasing demand for electric energy in portable electronic devices. The µ-SOFC is a less than 1 µm thin free-standing membrane. The membrane consists of ceramic and metallic thin film layers integrated on a micro-structurable substrate based on MEMS technologies. In this study, Foturan® glass ceramic and silicon µ-SOFCs substrates a

The increasing quality and durability of Solid Oxide Fuel Cells (SOFC) state-of-the-art materials renders the long-term testing of fuel cells difficult since considerably long equipment times are needed to obtain valuable results. Moreover, reproducibility issues are common due to the high sensitivity of the performance and degradation on the testing conditions. An original segmented cell configuration has been adopted in order to carry out four tests in parallel, thus decreasing the total experimental time

(001)-epitaxial SrTiO3 films were grown on (La, Sr)(Al, Ta)O-3 substrates for investigating the impact of biaxial strain on the antiferrodistortive (AFD) structural phase transition in SrTiO3. The films were fully constrained by the substrates, which resulted in the large in-plane compressive strain of -0.9%. The AFD transition temperature estimated using temperature controlled x-ray diffraction and transmission electron microscope was over 150K higher than the theoretical prediction, but rather supported t

Degradation observed on long term stack tests may be explained in part by microstructural changes of the electrodes. Particularly at the anode side, the coarsening of nickel particles will affect its performances. Increasing the metal particle size will first diminishes the Three-Phase Boundary (TPB) where fuel oxidation takes place, and secondly decrease the electronic conductivity [1]. In order to quantify the changes in anode microstructure, SEM images analysis is used. Some techniques can be time consum

In this paper, we present a modified transmission digital holographic microscope that can be used to image the state of polarization. The resulting device, called polarization digital holographic microscope (Pol-DHM), records in off-axis geometry the interference between two orthogonally polarized reference waves and the object wave transmitted by a microscopic sample and magnified by a microscope objective. A CCD camera records the resulting hologram. Using a single hologram, we reconstruct separately the

Information for phase identification may be gathered in the electron transmission microscope with spatial resolution down to the nanometre scale. Energy dispersive X-ray and electron energy loss spectrometries are based on inelastic electronsample interaction. They have the advantage to give a direct knowledge of the chemical nature of the atoms under the electron probe, sometimes also with valence and bonding, but concentrations are mean values over all atoms in the volume excited that may be insufficient

A versatile method for parallel nanoscale structures fabrication and patterning, using a combination of stencil-mask and pulsed-laser deposition (PLD) techniques is presented. A miniature shadow-mask with nano-apertures in a very thin microfabricated membrane (nanostencil) was separately manufactured and then, mechanically attached to the substrate of choice. In this way, complex oxides such as BaTiO3, BiFeO3 and PZT were deposited directly through the stencil’s holes onto various substrates (Si, Pt coated

A flexible method for simultaneous nanoscale structures fabrication and patterning is described, using a combination of stencil mask and pulsed-laser deposition (PLD) techniques. A miniature shadow-mask with nano-apertures in a very thin microfabricated membrane (nanostencil) was first manufactured and then, mechanically attached to the substrate of choice. To create free-standing membranes with arrays of apertures of different shapes and dimensions below 500 nm, a combination of advanced lithography or hig

We discuss the spectral signatures of strong electronic correlations and electron-phonon interactions in two representative low-dimensional systems. In the 2D compound 1T-TaSe2 a charge-density-wave (CDW) induces a narrowing of the conduction band, which triggers a surface metal-insulator (M-I) transition and the disappearance of the quasiparticle (QP) features. In the 1D blue bronze K0.3MoO3 strong interaction with the lattice lead to pseudogapped polaronic lineshapes, and the large mass renormalization ma

Surface nitriding of tetragonal zirconia (t-ZrO2) has been performed with the aim of combining the optical properties of zirconium nitride (ZrN) with the hardness and toughening properties of tetragonal zirconia. A high current d.c. arc plasma source has been used to create a reactive environment of atomic hydrogen and NH radicals. Plasma analysis showed that a highly reductive atmosphere is necessary to transform the tetragonal zirconia. X-ray diffraction and transmission electron microscopy analysis show

A simultaneous optimization of the design and operation of a district heating, cooling and power generation plant supplying a small stock of residential buildings has been undertaken with regards to cost and CO?2 emissions. The simulation of the plant considers a superstructure including a SOFC-GT combined cycle, a compression heat pump, a compression chiller and/or an absorption chiller, and an additional gas boiler. The Pareto-frontier obtained as the global solution of the optimization problem delivers t

In situ redox cycle of a nickel-YSZ fuel cell anode in an environmental transmission electron microscope

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Beyond the lateral resolution limit by phase imaging

Microfabrication of free-standing micro-solid oxide fuel cells on Foturan® and silicon substrates

Segmented cell testing for cathode parameter investigation

Antiferrodistortive Structural Phase Transition in Compressively-Strained Epitaxial SrTiO3 Film Grown on (La, Sr)(Al, Ta)O-3 Substrate

Methods for quantification of anode support microstructure

Birefringence measurement by use of digital holographic microscopy: examples with fiber optics and concrete samples

Identification of nano-phases: relative merit of local analysis techniques (HRTEM, nanodiffraction, EDS/EELS)

Nanostenciling: a Versatile Approach for Surfaces Patterning

Complex Oxide Nanostructures by Pulsed Laser Deposition through Nanostencils

Strong electron-electron and electron-phonon interactions in one- and two-dimensional solids

Nitriding of tetragonal zirconia in a high current d.c. plasma source

Multi-Criteria Optimization of a District Cogeneration Plant Integrating a Solid Oxide Fuel Cell - Gas Turbine Combined Cycle, Heat Pumps and Chillers