Publications related to Carbide-derived carbon

Tuning Pore Size in Graphene in the Angstrom Regime for Highly Selective Ion-Ion Separation

Kumar Varoon Agrawal, Kuang-Jung Hsu, Heng-Yu Chi, Kangning Zhao, Luis Francisco Villalobos Vazquez de la Parra, Shaoxian Li, Wan-Chi Lee, Yuyang Zhang

Zero-dimensional pores spanning only a few angstroms in size in two-dimensional materials such as graphene are some of the most promising systems for designing ion-ion selective membranes. However, the key challenge in the field is that so far a crack-free ...

Amer Chemical Soc2024

Multidimensional Electron Imaging of Catalyst Layer Materials

Robin Pierre Alain Girod

The proton exchange membrane fuel cell (PEMFC) is an important technology for clean power generation in a decarbonized hydrogen system and is notably envisioned for applications in heavy-duty transportation. However, for cost and performance competitivenes ...

EPFL2023

Molecular simulation on two-dimensional nanoporous material for energy-efficient separation

Mohammad Tohidivahdat

The energy-consumption by the chemical and petrochemical industry in the European Union (EU) accounts for about quarter of its energy footprint. Approximately half of this energy goes toward chemical separation, currently dominated by thermally-driven pro ...

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

Gas Separation Membranes with Atom-Thick Nanopores: The Potential of Nanoporous Single-Layer Graphene

Kumar Varoon Agrawal, Kuang-Jung Hsu, Cédric Karel J Van Goethem, Luis Francisco Villalobos Vazquez de la Parra, Deepu Joseph Babu

Gas separation is one of the most important industrial processes and is poised to take a larger role in the transition to renewable energy, e.g., carbon capture and hydrogen purification. Conventional gas separation processes involving cryogenic distillati ...

AMER CHEMICAL SOC2022

Multiscale microshaping of functionally graded polymer-derived SiCN ceramics

Lorenz Hagelüken

Polymer-derived ceramics (PDCs) exhibit excellent properties and are compatible with many shaping techniques due to the liquid character of the preceramic polymers (PCPs). Furthermore, their properties are adjustable by modifying the precursor composition ...

EPFL2022

Crystallization of Size-Selective Nanopores in Graphene for Gas Separation

Nanoporous single-layer graphene (N-SLG) membranes, owing to their single-atom thinness, have the potential to exceed the permeance and selectivity limits of gas separation membranes. However, two key issues in the top-down N-SLG synthesis need to be addre ...

EPFL2022

Mass transport of water vapor and ions from Å-scale graphene nanopores

Wan-Chi Lee

Hydrodynamics at the nanoscale involves both fundamental study and application of fluid and mass transport phenomena in nanometer-sized confinements. Nanopores in single-layer graphene can be highly attractive for exploring the molecular transport of gas a ...

EPFL2022

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

Atomic doping & coating for Electrocatalysis & Li-ion batteries

Albert Claude Jean-Pierre Daubry

Molybdenum atomic-doping on bio-waste derived nitrogen-doped conductive carbon electrocatalyst was synthesized and investigated for the dinitrogen reduction to ammonia in alkaline media. The assessment of the catalytic activity was found to be non-trivial ...

EPFL2022

Rapid screening of nanopore candidates in nanoporous single-layer graphene for selective separations using molecular visualization and interatomic potentials

Luc Sébastien Bondaz, Rohit Karnik

Nanoporous single-layer graphene is promising as an ideal membrane because of its extreme thinness, chemical resistance, and mechanical strength, provided that selective nanopores are successfully incorporated. However, screening and understanding the tran ...

AIP Publishing2021

Rapid Gas Transport from Block-Copolymer Templated Nanoporous Carbon Films

Kumar Varoon Agrawal, Kuang-Jung Hsu, Marina Micari, Xuekui Duan, Mostapha Dakhchoune, Luis Francisco Villalobos Vazquez de la Parra, Jing Zhao

Porous carbon films, attributed to their superior thermal and chemical robustness, are attractive for a number of applications. In the context of molecular separation, a major focus has been on films where the effective pore diameter is lower than 1 nm, e. ...

AMER CHEMICAL SOC2021

Millisecond lattice gasification for high-density CO2- and O2-sieving nanopores in single-layer graphene

Emad Oveisi, Kumar Varoon Agrawal, Marina Micari, Mounir Driss Mensi, Luis Francisco Villalobos Vazquez de la Parra, Mostapha Dakhchoune, Shiqi Huang, Shaoxian Li, Deepu Joseph Babu

Etching single-layer graphene to incorporate a high pore density with sub-angstrom precision in molecular differentiation is critical to realize the promising high-flux separation of similar-sized gas molecules, e.g., CO2 from N2. However, rapid etching ki ...

2021

Bottom-up synthesis of graphene films hosting atom-thick molecular-sieving apertures

Emad Oveisi, Kumar Varoon Agrawal, Kuang-Jung Hsu, Cédric Karel J Van Goethem, Victor Carle Adrien Boureau, Kangning Zhao, Luis Francisco Villalobos Vazquez de la Parra, Mostapha Dakhchoune, Shiqi Huang, Shaoxian Li, Mina Moradi

Incorporation of a high density of molecular-sieving nanopores in the graphene lattice by the bottom-up synthesis is highly attractive for high-performance membranes. Herein, we achieve this by a controlled synthesis of nanocrystalline graphene where incom ...

National Academy of Sciences2021

Etching nanopores in single-layer graphene with a sub-angstrom resolution in molecular sieving

Shiqi Huang

Single-layer graphene (SLG) membranes, hosting molecular-sieving nanopores have been regarded as the ultimate gas separation membranes, attributing to the fact that they are the thinnest possible molecular barrier. However, the expected attractive performa ...

EPFL2021

Spectroscopic view of ultrafast charge carrier dynamics in single- and bilayer transition metal dichalcogenide semiconductors

Jens Christian Johannsen

The quasiparticle spectra of atomically thin semiconducting transition metal dichalcogenides (TMDCs) and their response to an ultrafast optical excitation critically depend on interactions with the underlying substrate. Here, we present a comparative time- ...

ELSEVIER2021

Supported ruthenium nanoparticles for supercritical water gasification - synthesis, activity and stability

Christopher Marc Hunston

Supercritical water gasification (SCWG) is a promising and versatile technology for the conversion of a variety of wet biomass streams into renewable natural gas. In this work, the focus was set on methane production with the help of an active and stable m ...

EPFL2021

Crystal-Size-Induced Band Gap Tuning in Perovskite Films

Michael Graetzel, Wolfgang Richard Tress, Amita Ummadisingu, Simone Meloni

A comprehensive picture explaining the effect of the crystal size in metal halide perovskite films on their opto-electronic characteristics is currently lacking. We report that perovskite nanocrystallites exhibit a wider band gap due to concurrent quantum ...

Wiley-VCH Verlag GmbH2021

Multipulsed Millisecond Ozone Gasification for Predictable Tuning of Nucleation and Nucleation-Decoupled Nanopore Expansion in Graphene for Carbon Capture

Kumar Varoon Agrawal, Mounir Driss Mensi, Kuang-Jung Hsu, Heng-Yu Chi, Luis Francisco Villalobos Vazquez de la Parra, Mostapha Dakhchoune, Shiqi Huang, Guangwei He, Wan-Chi Lee

Predictable and tunable etching of angstrom-scale nanopores in single-layer graphene (SLG) can allow one to realize high-performance gas separation even from similar-sized molecules. We advance toward this goal by developing two etching regimes for SLG whe ...

2021

Processing and micro-mechanical characterization of multi-component transition MC carbides in iron

Andreas Mortensen, Goran Zagar, Léa Deillon, Marta Fornabaio, Lionel Michelet

We prepare multi-component transition monocarbides of chosen composition by arc-melting together a pre-alloy of the transition metals and cast iron. Based on the elements Ti, Ta, V, Nb and W, 51 different binary, ternary and quaternary compositions are pro ...

2021