Publications associées à In situ electron microscopy

Solution-based Cu+ transient species mediate the reconstruction of copper electrocatalysts for CO2 reduction

Raffaella Buonsanti, Anna Loiudice, Petru Pasquale Albertini, Jan Vávra, Gaétan Philippe Louis Ramona

Understanding metal surface reconstruction is of the utmost importance in electrocatalysis, as this phenomenon directly affects the nature of available active sites. However, its dynamic nature renders surface reconstruction notoriously difficult to study. ...

Nature Portfolio2024

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

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

Mechanistic study on the evolution of vacancies in graphene by oxidation by scanning tunneling microscopy

Shaoxian Li

Nanostructured graphitic materials, including graphene hosting Å to nanometer-sized pores, have attracted attention for various applications such as separations, sensors, and energy storage. Graphene with Å-scale pores is a promising next-generation materi ...

EPFL2023

Porous Nitride Light-Emitting Diodes

Anna Fontcuberta i Morral, Nicolas Tappy, Nuno Amador Mendez

A porous InGaN/GaN blue light-emitting diode is demonstrated using selective area sublimation. Transmission electron microscopy reveals that the structure is porous down to the Si substrate; however, the porosity is higher in the GaN buffer, while smaller ...

2022

Decoding the Mechanisms of Phase Transitions from In Situ Microscopy Observations

Vasiliki Tileli, Reinis Ignatans

Analysis of the temperature- and stimulus-dependent imaging data toward elucidation of the physical transformations is an ubiquitous problem in multiple fields. Here, temperature-induced phase transition in BaTiO3 is explored using the machine learning ana ...

WILEY-V C H VERLAG GMBH2022

Microsecond melting and revitrification of cryo samples with a correlative light-electron microscopy approach

Marcel Drabbels, Gabriele Bongiovanni, Oliver Florian Harder

We have recently introduced a novel approach to time-resolved cryo-electron microscopy (cryo-EM) that affords microsecond time resolution. It involves melting a cryo sample with a laser beam to allow dynamics of the embedded particles to occur. Once the la ...

2022

Time-Resolved Transmission Electron Microscopy: Instrumentation and Applications

Pavel Olshin

In recent decades, in situ electron microscopy has attracted considerable attention. The method enables real time observations of the transformations of nanoparticles under various stimuli with atomic spatial resolution. Time-resolved electron microscopy a ...

EPFL2021

Cu/Metal Oxide Hybrid Nanocrystals as Electrocatalysts for the CO2 Reduction Reaction

Seyedehbehnaz Varandili

The electrochemical CO2 reduction reaction (CO2RR) is envisioned to play a significant role in achieving carbon neutrality while contributing to storing renewable energies. Cu-based materials are among the most promising electrocatalysts. However, 16 diffe ...

EPFL2021

Challenges and Applications to Operando and In Situ TEM Imaging and Spectroscopic Capabilities in a Cryogenic Temperature Range

Vasiliki Tileli, Martial Duchamp, Reinis Ignatans

In this Account, we describe the challenges and promising applications of transmission electron microscopy (TEM) imaging and spectroscopy at cryogenic temperatures. Our work focuses on two areas of application: the delay of electron-beam-induced degradatio ...

AMER CHEMICAL SOC2021

Advanced analytical electron microscopy applied to Solid Oxide Cell materials and their degradation

Stéphane François Jean Poitel

Electron microscopy offers a wide range of techniques to study materials. Environmental Scanning Electron Microscopy (ESEM), in particular, allows the characterisation of samples at high-temperature using a laser heating stage, and under various gaseous at ...

EPFL2020

Visualizing the importance of oxide-metal phase transitions in the production of synthesis gas over Ni catalysts

Stéphane François Jean Poitel

Synthesis gas, composed of H-2 and CO, is an important fuel which serves as feedstock for industrially relevant processes, such as methanol or ammonia synthesis. The efficiency of these reactions depends on the H-2 : CO ratio, which can be controlled by a ...

2020

Charge/discharge cycling of Li1+x(Ni0.6Co0.2Mn0.2)1−xO2 primary particles performed in a liquid microcell for transmission electron microscopy studies

Vasiliki Tileli, Tzu-Hsien Shen, Robin Pierre Alain Girod, Jing Hou

Ni-rich layered oxides are promising positive electrodes for fulfillment of government and industry targets for lithium-ion-battery-operated electric mobility purposes. Apart from ongoing research focusing on their design and material production, advanced ...

2020

Insights into the Photocatalytic Bacterial Inactivation by Flower-Like Bi2WO6 under Solar or Visible Light, Through in Situ Monitoring and Determination of Reactive Oxygen Species (ROS)

César Pulgarin, Juan Kiwi, Sami Rtimi, Stefanos Giannakis, Minoo Karbasi

This study addresses the visible light-induced bacterial inactivation kinetics over a Bi2WO6 synthesized catalyst. The systematic investigation was undertaken with Bi2WO6 prepared by the complexation of Bi with acetic acid (carboxylate) leading to a flower ...

2020

Evidence for a dual mechanism in the TiO2/CuxO photocatalyst during the degradation of sulfamethazine under solar or visible light: Critical issues

César Pulgarin, Juan Kiwi, Sami Rtimi, Jiajie Yu

This study presents the photocatalytic degradation of sulfamethazine (SMT) on TiO2/CuxO nanotubes (NTs) by a differentiated mechanism under low intensity solar light and indoor visible light irradiation. In the presence of TiO2/CuxO nanotubes, the SMT-degr ...

ELSEVIER SCIENCE SA2019

Picture of the wet electron: a localized transient state in liquid water

Alfredo Pasquarello, Francesco Ambrosio, Michele Pizzochero

A transient state of the excess electron in liquid water preceding the development of the solvation shell, the so-called wet electron, has been invoked to explain spectroscopic observations, but its binding energy and atomic structure have remained highly ...

2019

Electrochemical Behavior of Carbon Electrodes for In Situ Redox Studies in a Transmission Electron Microscope

Vasiliki Tileli, Robin Pierre Alain Girod, Nikolaos Nianias

Electrochemical liquid cell transmission electron microscopy (TEM) is a unique technique for probing nanocatalyst behavior during operation for a range of different electrocatalytic processes, including hydrogen evolution reaction (HER), oxygen evolution r ...

CAMBRIDGE UNIV PRESS2019

Gate-tunable Scanning Tunneling Microscope as a tool for performing single-molecule chemistry

Shai Mangel

The atomic level understanding and control of the electron transport has important advantages for many applications, such as molecular electronics, solar cells and sensors. The target of my Ph.D. work is to investigate electronic and chemical properties of ...

EPFL2019

In-Situ Observation of Co-Ce Coated Metallic Interconnect Oxidation Combined with High-Resolution Post Exposure Analysis

Jan Van Herle, Stéphane François Jean Poitel, Cécile Hébert

Oxidation of Sanergy SSHT steel with Ce-Co coating, used as interconnect material, was observed in-situ in a modified environmental scanning electron microscope (ESEM) at nominal temperature between 800°C and 900°C under 33Pa of oxygen, for different durat ...

2017

Nanoscale structural oscillations in perovskite oxides induced by oxygen evolution

Vasiliki Tileli

Understanding the interaction between water and oxides is critical for many technological applications, including energy storage, surface wetting/self-cleaning, photocatalysis and sensors. Here, we report observations of strong structural oscillations of B ...

Nature Publishing Group2017