Publications associées à Abnormal Grain Growth in AlScN Thin Films Induced by Complexion Formation at Crystallite Interfaces

Spinel Protective Coatings for Solid Oxide Cell (SOC) Interconnects (ICs)

Abstract The degradation of metal interconnects (ICs) in Solid Oxide Cells (SOCs) primarily results from chromium (Cr) oxide scale growth on stainless-steel substrates, causing ohmic loss and air-side electrode poisoning by Cr. This thesis addresses these ...

EPFL2024

Optimizing Atomic Layer Deposition Processes with Nanowire-Assisted TEM Analysis

Johann Michler, Ivo Utke, Xavier Maeder

Atomic layer deposition (ALD) is one of the premier methods to synthesize ultra-thin materials on complex surfaces. The technique allows for precise control of the thickness down to single atomic layers, while at the same time providing uniform coverage ev ...

Wiley2024

Microsecond Time-Resolved Cryo-Electron Microscopy

Oliver Florian Harder

Recently, single-particle cryo-electron microscopy emerged as a technique capable of determining protein structures at near-atomic resolution and resolving protein dynamics with a temporal resolution ranging from second to milliseconds. This thesis describ ...

EPFL2024

Polydopamine-coated photoautotrophic bacteria for improving extracellular electron transfer in living photovoltaics

Fabian Fischer, Ardemis Anoush Boghossian, Charlotte Elisabeth Marie Roullier, Melania Reggente, Mohammed Mouhib, Patricia Brandl, Hanxuan Wang

Living photovoltaics are microbial electrochemical devices that use whole cell–electrode interactions to convert solar energy to electricity. The bottleneck in these technologies is the limited electron transfer between the microbe and the electrode surfac ...

2024

Structural study of nickelate based heterostructures

Jean-Marc Triscone, Duncan Thomas Lindsay Alexander, Bernat Mundet, Chih-Ying Hsu

Heterostructures consisting of SmNiO3 and NdNiO3 alternating layers with additional LaAlO3 spacer layers were grown and fully characterized by means of x-ray diffraction, atomic force microscopy, and scanning transmission electron microscopy. A change in t ...

Aip Publishing2024

Simple shear extrusion versus equal channel angular pressing: A comparative study on the microstructure and mechanical properties of an Mg alloy

Cyril Cayron, Roland Logé, Aryan Rezaei Rad

Two severe plastic deformation (SPD) techniques of simple shear extrusion (SSE) and equal channel angular pressing (ECAP) were employed to process an extruded Mg -6Gd -3Y -1.5Ag (wt%) alloy at 553 K for 1, 2, 4 and 6 passes. The microstructural evolutions ...

KEAI PUBLISHING LTD2023

Vacancy segregation and intrinsic coordination defects at (111) twist grain boundaries in diamond

Christian Brandl, Carolina Baruffi

High radiation damage resistance has become increasingly important for applications of functional materials in harsh environments. The high radiation damage resistance diamond cubic carbon is a unique material which is considered for radiation environments ...

Pergamon-Elsevier Science Ltd2023

Tensile and creep-rupture response of additively manufactured nickel-based superalloy CM247LC

Christian Leinenbach, Rafal Wróbel

Tensile and creep rupture properties of crack-free CM247LC alloy, processed via laser powder bed fusion, have been characterised in this work at temperatures up to 1000 & DEG;C. The subject alloy matches or even exceeds the tensile performance of its direc ...

ELSEVIER2023

Atomic scale volume and grain boundary diffusion elucidated by in situ STEM

Johann Michler, Amit Sharma, Laszlo Pethö, Xavier Maeder

Diffusion is one of the most important phenomena studied in science ranging from physics to biology and, in abstract form, even in social sciences. In the field of materials science, diffusion in crystalline solids is of particular interest as it plays a p ...

Nature Portfolio2023

The influence of lattice misfit on screw and edge dislocation-controlled solid solution strengthening in Mo-Ti alloys

William Curtin, Carolina Baruffi, You Rao

Mo-Ti alloys form solid solutions over a wide range of compositions, with lattice misfit parameters increasing significantly with titanium content. This indicates a strong increase in the critical stress for edge dislocation motion. Here, we probe the tran ...

SPRINGERNATURE2023

Rapid grain boundary diffusion in foraminifera tests biases paleotemperature records

Lukas Baumgartner, Anders Meibom, Jaroslaw Hubert Stolarski, Arthur Adams, Deyanira Graciela Cisneros Lazaro, Jinming Guo

The paleoseawater temperature record from the oxygen isotope compositions of fossil foraminifera tests may be biased by up to about 1 degrees C due to grain-boundary diffusion alone, according to isotope exchange experiments on foraminifera tests. The oxyg ...

2023

Origin of the enhanced pseudo-elasticity of additively manufactured Fe-17Mn-5Si-4Ni-10Cr-(V, C) shape memory alloy fabricated by laser powder bed fusion

Christian Leinenbach, Irene Ferretto

This study investigated the origin of the enhanced pseudo-elasticity of additively manufactured vanadium carbide-containing Fe-based shape memory alloys. The aged samples with two different starting microstructures, as-built and solution-treated, showed co ...

Elsevier Science Sa2023

Highly Efficient and Air-Stable Inorganic Perovskite Solar Cells Enabled by Polylactic Acid Modification

Feng Liu, Yong Ding

Inorganic perovskite solar cells (PSCs) suffer from serious carrier recombination and open-circuit voltage loss because of surface defects and unfavorable energy level alignment. Herein, a polylactic acid (PLA) modification approach to improve the performa ...

WILEY-V C H VERLAG GMBH2023

Diffusion timescale conundrum in contact metamorphism: Oxygen isotope and trace element profiles in dolomite

Lukas Baumgartner, Anders Meibom, Stéphane Laurent Escrig, Florence Bégué

Successful application of diffusion chronometry is based on detailed knowledge of diffusion parameters obtained from laboratory experiments, which also need to be upscaled to be applied to natural samples. While generally applicable, several examples of di ...

PERGAMON-ELSEVIER SCIENCE LTD2023

In Situ and Time-Resolved Transmission Electron Microscopy of Nanoscale Processes

Chengcheng Yan

Observing the fast dynamics of nanoscale systems is crucial in order to understand and ultimately control their behavior. Characterizing these dynamic processes requires techniques with atomic spatial resolution and a temporal resolution that matches the t ...

EPFL2023

Effect of Mo addition on the mechanical and tribological properties of magnetron sputtered TiN films

Sami Rtimi

Ternary-based titanium nitride (TiN) thin films have drawn attention toward rational applications due to their wear resistance, high hardness, and corrosion resistance. The influence of Mo content on the structural, tribo-logical, and mechanical properties ...

ELSEVIER SCIENCE SA2023

Electron imaging of gas diffusion electrodes for proton exchange membrane fuel cells

Michele Bozzetti

The current energy crisis demands the development of new sustainable energy sources and devices with low environmental impact, including in the field of electrochemical cells. Mass transport limitations can reduce the overall performance of the device by l ...

EPFL2023

Impact of Annealing on ZrO2 Nanotubes for Photocatalytic Application

Sami Rtimi

This work aims to study the structural, optical, and photocatalytic properties of ZrO2 nanotubes (NTs) that have been synthesized using the electrochemical anodization method. The structural and morphological characteristics of unannealed and annealed (400 ...

MDPI2023

Microstructure et usinabilité d'alliages de titane béta-métastable

Loïc Favre

Titanium has become in recent years an interesting material in many applications that require a combination of high mechanical properties and low density. It has the peculiarity of undergoing an allotropic transformation at 882°C. Below this temperature, ...

EPFL2023

Towards near-atomic resolution imaging of microsecond nanoscale dynamics

Gabriele Bongiovanni

Time-resolved electron microscopy has made significant progress in recent years, with some groups now working on instruments that offer attosecond temporal resolution. While much of the research in the field revolves around the improvement of temporal reso ...

EPFL2023