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Aïcha Hessler-Wyser

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Related publications (95)

Page 2 of 5

Enhancing the optoelectronic properties of amorphous zinc tin oxide by subgap defect passivation: A theoretical and experimental demonstration

Christophe Ballif, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Monica Morales Masis, Jakub Holovsky, Oscar Esteban Rucavado Leandro, Federica Landucci

The link between sub-bandgap states and optoelectronic properties is investigated for amorphous zinc tin oxide (a-ZTO) thin films deposited by RF sputtering. a-ZTO samples were annealed up to 500 °C in oxidizing, neutral, and reducing atmospheres before ch ...

American Physical Society2017

A TEM study of Ni interfaces formed during activation of SOFC anodes in H 2 : Influence of grain boundary symmetry and segregation of impurities

Jan Van Herle, Cécile Hébert, Aïcha Hessler-Wyser, Quentin Thomas Jeangros

The electrochemical properties of a solid oxide fuel cell depend on many parameters, including – on the anode side – the connectivity of the Ni network and the segregation of impurities at active points. In this work, advanced scanning transmission electro ...

2016

UV-nanoimprint lithography and large area roll-to-roll texturization with hyperbranched polymer nanocomposites for light-trapping applications

Jan-Anders Edvin Maansson, Yves Leterrier, Aïcha Hessler-Wyser, Marina Aymara González Lazo, Philippe Couty, Caroline Calderone

Light-trapping textures were produced in hyperbranched polymer (HBP) silica nanocomposites using a UV-nanoimprint lithography (UVNIL) replication method, either in batch or roll-to-roll processes. The hardness of the HBP was found to increase by a factor o ...

Elsevier2012

On Potential Application of Coated Ferritic Stainless Steel Grades K41X and K44X in SOFC/HTE Interconnects

Jan Van Herle, Aïcha Hessler-Wyser

K41X is a ferritic stainless steel grade which was successfully developed in exhaust gas manifold where the temperature could reach 950°C. It contains about 18% wt of chromium and it is stabilized with both titanium and niobium to warranty a good weldabili ...

2011

Experimental and Theoretical Investigation of Degradation Mechanisms in SOFC Electrodes

Jan Van Herle, Christos Comninellis, Aïcha Hessler-Wyser, Antonin Faes, Pietro Tanasini

Performance degradation data obtained on single solid oxide fuel cells tested at 850°C with air and humidified H2 and using Ni-YSZ anode supported cells are presented. Microscopic investigation is carried out on both anode and cathode to quantify variation ...

2009

Evaluation of secondary electron intensities for dopant profiling in ion implanted semiconductors: a correlative study combining SE, SIMS and ECV methods

Aïcha Hessler-Wyser, Franz-Josef Haug, Quentin Thomas Jeangros, Mario Joe Lehmann, Philippe Wyss, Audrey Marie Isabelle Morisset

This study evaluates the secondary electron (SE) dopant contrast in scanning electron microscopy (SEM) and helium ion microscopy (HIM) on boron implanted silicon sample. Complementary techniques like secondary ion mass spectrometry and electrochemical capa ...

IOP PUBLISHING LTD2021

Operando analysis of a solid oxide fuel cell by environmental transmission electron microscopy

Jan Van Herle, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Stefan Diethelm, Cédric Frantz

Correlating the microstructure of an energy conversion device to its performance is often a complex exercise, notably in solid oxide fuel cell research. Solid oxide fuel cells combine multiple materials and interfaces that evolve in time due to high operat ...

Nature Portfolio2023

Linking Nanoscopic Insights to Millimetric-Devices in Formamidinium-Rich Perovskite Photovoltaics

Christophe Ballif, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Mostafa Rabie Shlaly Bahr Othman

Halide-perovskite semiconductors have a high potential for use in single-junction and tandem solar cells. Despite their unprecedented rise in power conversion efficiencies (PCEs) for photovoltaic (PV) applications, it remains unclear whether perovskite sol ...

Wiley-V C H Verlag Gmbh2024

Passivating contact-based tunnel junction Si solar cells using machine learning for tandem cell applications

Christophe Ballif, Franz-Josef Haug, Aïcha Hessler-Wyser, Audrey Marie Isabelle Morisset

Tandem solar cells are a key technology for exceeding the theoretical efficiency limit of single-junction cells. One of the most promising combinations is the silicon-perovskite tandem cells, considering their potential for high efficiency, fabrication on ...

ELSEVIER2023

Direct Imaging of Dopant Distribution in Polycrystalline ZnO Films

Christophe Ballif, Cécile Hébert, Aïcha Hessler-Wyser, Duncan Thomas Lindsay Alexander, Stéphane Laurent Escrig, Monica Morales Masis, Sylvain Nicolay, Martin Ledinsky, Arthur Brian Aebersold

Two fundamental requirements of transparent conductive oxides are high conductivity and low optical absorptance, properties strongly dependent on the free-carrier concentration of the film. The free carrier concentration is usually-tuned by the addition of ...

Amer Chemical Soc2017

Glass-Forming Exogenous Silicon Contamination in Solid Oxide Fuel Cell Cathodes

Jan Van Herle, Aïcha Hessler-Wyser, Josef Andreas Schuler, Zacharie Wuillemin

Spatially resolved analyses, by energy-dispersive X-ray spectroscopy (EDS) scanning electron microscopy (SEM), allowed the quantification of exogenous Si contamination in a solid oxide fuel cell (SOFC) cathode after operation. The Si quantification, taking ...

Electrochemical Society2011

Blade-Coating of High Crystallinity Cesium-Formamidinium Perovskite Formulations

Anaël Morgane Jaffrès, Christophe Ballif, Aïcha Hessler-Wyser, Christian Michael Wolff, Mostafa Rabie Shlaly Bahr Othman

Up-scalable coating processes need to be developed to manufacture efficient and stable perovskite-based solar modules. In this work, we combine two Lewis base additives (N,N′-dimethylpropyleneurea and thiourea) to fabricate high-quality Cs0.15FA0.85PbI3 pe ...

2024

In situ Reduction and Oxidation of Nickel from Solid Oxide Fuel Cells in a Transmission Electron Microscope

Jan Van Herle, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Antonin Faes

Environmental transmission electron microscopy was used to characterize in situ the reduction and oxidation of nickel from a Ni/YSZ solid oxide fuel cell anode support between 300-500°C. The reduction is done under low hydrogen pressure. The reduction init ...

2009

Tuning the Optoelectronic Properties of ZnO:Al by Addition of Silica for Light Trapping in High-Efficiency Crystalline Si Solar Cells

Christophe Ballif, Stefaan De Wolf, Aïcha Hessler-Wyser, Björn Niesen, Monica Morales Masis, Ali Dabirian

Highly transparent electrodes with a well-tuned refractive index are essential for a wide range of optoelectronic devices, such as light emitting diodes and solar cells. Here, it is shown that the transparency of ZnO:Al can be improved and its refractive i ...

Wiley-Blackwell2016

Growth of intermetallic compounds in the Au-In system: Experimental study and 1-D modelling

Michel Rappaz, Aïcha Hessler-Wyser, Léa Deillon

The gold indium system is of primary interest for bonding processes such as solid liquid interdiffusion bonding. In order to optimize the manufacturing parameters, it is essential to know which intermetallic compounds (IMCs) are formed when solid Au and li ...

Elsevier2014

X-ray Imaging and Analysis of 3D Microstructural Changes in Aged Ni-YSZ Anode

Jan Van Herle, Aïcha Hessler-Wyser, Antonin Faes

Ni-YSZ anode supports were used to fabricate test cells composed of yttria-stabilised zirconia (YSZ) electrolyte and lanthanum strontium ferrite (LSF) or lanthanum strontium manganite (LSM) / YSZ cathodes. These cells were operated at 720 °C at an average ...

2011

Stress tolerance of lightweight glass-free PV modules for vehicle integration

Kléber Nicolet-dit-Félix, Christophe Ballif, Matthieu Despeisse, Aïcha Hessler-Wyser, Jacques Levrat, Antonin Faes, Gianluca Cattaneo, Umang Bhupatrai Desai, Fahradin Mujovi

Electric vehicles (EVs) currently dominate the sales in the automotive market. A big leap in this market can be made by developing a photovoltaic product that can be integrated to an EV, as it can boost the driving range of the EV while reducing the chargi ...

Edp Sciences S A2024

Three-dimensional microstructural changes in the Ni-YSZ solid oxide fuel cell anode during operation

Jan Van Herle, Aïcha Hessler-Wyser, Antonin Faes

Microstructural evolution in solid oxide fuel cell (SOFC) cermet anodes has been investigated using X-ray nanotomography along with differential absorption imaging. SOFC anode supports composed of Ni and yttria-stabilized zirconia (YSZ) were subjected to e ...

2012

Passivating Polysilicon Recombination Junctions for Crystalline Silicon Solar Cells

Christophe Ballif, Franz-Josef Haug, Aïcha Hessler-Wyser, Quentin Thomas Jeangros, Andrea Ingenito, Mario Joe Lehmann, Philippe Wyss, Audrey Marie Isabelle Morisset

Polysilicon recombination junctions whose n-type bottom layers double as a passivating contact to the silicon surface are investigated. Such recombination junctions are a key element in the interconnection of tandem devices with a silicon bottom cell, and ...

2021

Design of experiment approach applied to reducing and oxidizing tolerance of anode supported solid oxide fuel cell. Part I: Microstructure optimization

Jan Van Herle, Aïcha Hessler-Wyser, Antonin Faes, Jean-Marie Fuerbringer

The main drawback of Ni/YSZ anode supports for solid oxide fuel cell application is their low tolerance to reducing and oxidizing (RedOx) atmosphere changes, owing to the Ni/NiO volume variation. This work describes a structured approach based on design of ...

Elsevier2011