Publications associées à FB-REDA: fragment-based decomposition analysis of the reorganization energy for organic semiconductors

Molecular hypergraph neural networks

Graph neural networks (GNNs) have demonstrated promising performance across various chemistry-related tasks. However, conventional graphs only model the pairwise connectivity in molecules, failing to adequately represent higher order connections, such as m ...

Aip Publishing2024

Shortwave Infrared-Sensitive, Narrowband Organic Upconversion Devices with a Gain

Wei-Hsu Hu

Sensing and imaging of light in the shortwave infrared (SWIR) range is increasingly used in various fields, including bio-imaging, remote sensing, and semiconductor process control. SWIR-sensitive organic photodetectors (OPDs) are promising because organic ...

EPFL2024

Assessing the Charge Carrier Dynamics at Hybrid Interfaces of Organic Photoanodes for Solar Fuels

Kevin Sivula, Yongpeng Liu, Han-Hee Cho, Alexander Wieczorek

Organic semiconductors (OSCs) have emerged as promising active layers for photoanodes to drive photoelectrochemical (PEC) oxidation reactions. Interfacing an OSC with an inorganic electron transport layer (ETL) is key to enabling both high performance and ...

Amer Chemical Soc2024

Controlling On-Surface Photoactivity: The Impact of π-Conjugation in Anhydride-Functionalized Molecules on a Semiconductor Surface

Karl-Heinz Ernst, Christian Wäckerlin

On-surface synthesis has become a prominent method for growing low-dimensional carbon-based nanomaterials on metal surfaces. However, the necessity of decoupling organic nanostructures from metal substrates to exploit their properties requires either trans ...

Wiley-VCH Verlag GmbH2024

Charge-Transfer States in Organic Nanowires

Lucile Annie Chassat

Charge separation processes in organic semiconductors play a pivotal role in diverse applications ranging from photovoltaics to photocatalysis. Understanding these mechanisms, particularly the role of hybrid charge-transfer (CT) states, is essential for ad ...

EPFL2024

Drift-Diffusion Simulations of Charge Transport and Trap Dynamics in Organic Semiconductor Materials

Camilla Arietta Vael-Garn

Polymeric semiconductors have gained significant attention in the field of organic electronics due to their unique properties and potential applications. Through their ability to transport charge carriers and to absorb or emit light, they have attracted mu ...

EPFL2023

Semiconductor-based device architectures in multimaterial fibers

William Nicolas Duncan Esposito

Semiconductor materials have given rise to today's digital technology and consumer electronics. Widespread adoption is closely linked to the ability to process and integrate them in devices at scale. Where flexibility and large surfaces are required, such ...

EPFL2023

Photoelectrochemical Cell Engineering for Solar Energy Conversion

Dan Zhang

Solar energy is the most abundant energy source, harnessing solar energy holds the solution to the challenge of increasing global energy demand and reducing our dependence on fossil fuels. Photovoltaics which directly convert solar energy into electricity ...

EPFL2023

New ultrahigh-speed device concepts: from THz nanoplasma devices to glass-like electronics for neuromorphic computation

Mohammad Samizadeh Nikooytabalvandani

There is a never-ending push for electronic systems to provide faster operation speeds, higher energy efficiencies, and higher power capabilities at smaller scales. These requirements are apparent in different areas of electronics, from radiofrequency (RF) ...

EPFL2023

The nanoscale impact of individual nonradiative point defects on InGaN/GaN quantum wells

Thomas Fjord Kjaersgaard Weatherley

Today's world depends on optoelectronic devices: light-emitting diodes illuminate our houses and backlight the displays on our gadgets, while laser diodes underpin fibre-optic communication. Such optoelectronic devices rely on crystalline semiconductor het ...

EPFL2023

Momentum-Space Imaging of Ultra-Thin Electron Liquids in δ-Doped Silicon

Nicolò D'Anna, Gabriel Aeppli

Two-dimensional dopant layers (δ-layers) in semiconductors provide the high-mobility electron liquids (2DELs) needed for nanoscale quantum-electronic devices. Key parameters such as carrier densities, effective masses, and confinement thicknesses for 2DELs ...

WILEY2023

Electrically tunable dipolar interactions between layer-hybridized excitons

Andras Kis, Fedele Tagarelli, Edoardo Lopriore

Transition-metal dichalcogenide bilayers exhibit a rich exciton landscape including layer-hybridized excitons, i.e. excitons which are of partly intra- and interlayer nature. In this work, we study hybrid exciton-exciton interactions in naturally stacked W ...

ROYAL SOC CHEMISTRY2023

Engineering of PEM-PEC photocathodes for solar-driven hydrogen production

Marina Caroline Michèle Caretti

Earth has always been in perpetual evolution, but today we must face its rapid change due to human activity. The intensification of industrial activities and transportation to support our modern lifestyles are the main causes of climate change and the adve ...

EPFL2022

Organic Semiconductors For Photoelectrochemical Applications

Arvindh Sekar

The capture and conversion of solar energy into other useful forms has been the topic of discussion for the past few decades, accentuated by the need to combat climate change and face the challenge of non-renewability of conventional sources of fuel for ou ...

EPFL2022

Selective area epitaxy of GaAs: the unintuitive role of feature size and pitch

Anna Fontcuberta i Morral, Lucas Güniat, Martin George Friedl, Nicholas Paul Morgan, Akshay Balgarkashi, Didem Dede, Elif Nur Dayi, Valerio Piazza, Vladimir Dubrovskii

Selective area epitaxy (SAE) provides the path for scalable fabrication of semiconductor nanostructures in a device-compatible configuration. In the current paradigm, SAE is understood as localized epitaxy, and is modelled by combining planar and self-asse ...

IOP Publishing Ltd2022

Bulk Heterojunction Organic Semiconductor Photoanodes: Tuning Energy Levels to Optimize Electron Injection

Jun Ho Yum, Kevin Sivula, Nestor Guijarro Carratala, Arvindh Sekar, Liang Yao, Barbara Alexandra Primera Darwich, Yongpeng Liu, Han-Hee Cho, Juan Manuel Moreno Naranjo

The use of a bulk heterojunction of organic semiconductors to drive photoelectrochemical water splitting is an emerging trend; however, the optimum energy levels of the donor and acceptor have not been established for photoanode operation with respect to e ...

AMER CHEMICAL SOC2022

Single molecule fluorescence and phosphorescence studies using a scanning tunneling microscope

Abhishek Grewal

This thesis investigates novel single-molecule luminescence phenomena at their inherent, sub-molecular length scale. The microscopic understanding of luminescence processes will be crucial for the continued improvement of organic optoelectronic and semicon ...

EPFL2022

Scrutinizing thermally stimulated current transients originating from trapped charges in organic semiconductors: A drift-diffusion study

Frank Nüesch, Beat Ruhstaller

Thermally stimulated current (TSC) is a widely used technique to assess trap states and extract their density, energy, and capture rate using analytical expressions. In many cases, the latter are derived from physical models pertaining to inorganic semicon ...

AIP Publishing2022

Defects in III-N LEDs: experimental identification and impact on electro-optical characteristics

Jean-François Carlin, Nicolas Grandjean, Mauro Mosca, Camille Haller

III-N light-emitting-diodes (LEDs) are subject of intense investigations, thanks to their high efficiency and great reliability. The quality of the semiconductor material has a significant impact on the electro-optical performance of LEDs: for this reason, ...

SPIE-INT SOC OPTICAL ENGINEERING2022

Electrical control of glass-like dynamics in vanadium dioxide for data storage and processing

Andras Kis, Andreas Schueler, Anna Krammer, Elison de Nazareth Matioli, Reza Soleiman Zadeh Ardebili, Mohammad Samizadeh Nikooytabalvandani, Philip Johannes Walter Moll, Guilherme Migliato Marega

Metal–oxide–semiconductor junctions are the building blocks of modern electronics and can provide a variety of functionalities, from memory to computing. The technology, however, faces constraints in terms of further miniaturization and compatibility with ...

2022