Publications related to Covalent bonded bilayers from germanene and stanene with topological giant capacitance effects

Functionalized Å-scale Pores in Graphene for Carbon Capture

Single-layer graphene, hosting a high density of functionalized molecular-sieving atom-thick pores, is considered to be an excellent material for gas separation membranes. These functionalized atom-thick pores enable the shortest transport pathway across t ...

EPFL2024

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

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

Electrochemical-repaired porous graphene membranes for precise ion-ion separation

Kumar Varoon Agrawal, Heng-Yu Chi, Kuang-Jung Hsu, Kangning Zhao, Shuqing Song, Zongyao Zhou

The preparation of atom-thick porous lattice hosting & Aring;-scale pores is attractive to achieve a large ion-ion selectivity in combination with a large ion flux. Graphene film is an ideal selective layer for this if high-precision pores can be incorpora ...

Nature Portfolio2024

Topological Effects in Carbon-based Two-dimensional Nanostructures

Yifei Guan

Recent advances on low-dimensional and topological materials has greatly inspired the research in condensed matter physics. This thesis is devoted to the computational and theoretical study of topological effects in two-dimensional materials, especially na ...

EPFL2023

In-situ atomic level observation of the strain response of graphene lattice

Klaus Kern, Jz -Yuan Juo

Strain is inevitable in two-dimensional (2D) materials, regardless of whether the film is suspended or supported. However, the direct measurement of strain response at the atomic scale is challenging due to the difficulties of maintaining both flexibility ...

Nature Portfolio2023

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

Ultralong 100 ns spin relaxation time in graphite at room temperature

László Forró, Bálint Náfrádi, Péter Szirmai, Bence Gábor Márkus

Graphite has been intensively studied, yet its electron spins dynamics remains an unresolved problem even 70 years after the first experiments. The central quantities, the longitudinal (T-1) and transverse (T-2) relaxation times were postulated to be equal ...

Nature Portfolio2023

Charging and Electric Field Effects on Hydrogen Molecules Physisorbed on Graphene

Klaus Kern, Shai Mangel, Alessio Scavuzzo, Tobias Wollandt

Molecular hydrogen adsorbed on graphene was investigated by analyzing rotational excitation spectra obtained with a gate-tunable scanning tunneling microscope (STM). Through the shift of the rotational excitation energy, the tunability of physisorbed H2 on ...

AMER CHEMICAL SOC2023

Resonant Transducers Consisting of Graphene Ribbons with Attached Proof Masses for NEMS Sensors

Luis Guillermo Villanueva Torrijo, Daniel Moreno Garcia

The unique mechanical and electrical properties of graphene make it an exciting material for nanoelectromechanical systems (NEMS). NEMS resonators with graphene springs facilitate studies of graphene's fundamental material characteristics and thus enable i ...

Amer Chemical Soc2023

Cotton yarns decorated with hydrothermally reduced graphene oxide for flexible supercapacitors

Xing Wang, Dou Du, Lin Li

Cotton fibers, a natural cellulose, have played a critical role in the development of wearable energy storage, owning to their wearability, integrability, eco-benignity, and cost effectiveness. Graphene, a two-dimensional carbon material, possesses excelle ...

Elsevier2023

Selective Growth of van der Waals Heterostructures Enabled by Electron-Beam Irradiation

Aleksandra Radenovic, Michal Daniel Macha

Van der Waals heterostructures (vdWHSs) enable the fabricationof complex electronic devices based on two-dimensional (2D) materials.Ideally, these vdWHSs should be fabricated in a scalable and repeatableway and only in the specific areas of the substrate t ...

AMER CHEMICAL SOC2023

Multi-scale characterization and modeling of notched strength and translaminar fracture in hybrid thin-ply composites based on different carbon fiber grades

Guillaume Clément Broggi

Owing to their high specific stiffness and strength, Carbon Fiber Reinforced Composites (CFRP) are ideal candidates for the development of lightweight high-performance structures. Within this family, thin-ply composites allow for wider design freedom and p ...

EPFL2023

Effects of thermal, mechanical, and electrostatic perturbations on lipid membrane hydration investigated by second harmonic imaging

Seonwoo Lee

Hydrated lipid bilayer membranes are crucial components of cells and organelles, serving as the outer boundary that separates the cellular components from the extracellular environment. Lipid membranes regulate their structures and functions by dynamically ...

EPFL2023

Liposomes and Lipid Droplets Display a Reversal of Charge-Induced Hydration Asymmetry

Sylvie Roke, Nathan Dupertuis, Saranya Pullanchery Sankara Narayanan

The unique properties of water are critical for life. Water molecules have been reported to hydrate cations and anions asymmetrically in bulk water, being a key element in the balance of biochemical interactions. We show here that this behavior extends to ...

Amer Chemical Soc2023

Infrared-active phonons in one-dimensional materials and their spectroscopic signatures

Nicola Marzari, Thibault Daniel Pierre Sohier, Norma Rivano

Dimensionality provides a clear fingerprint on the dispersion of infrared-active, polar-optical phonons. For these phonons, the local dipoles parametrized by the Born effective charges drive the LO-TO splitting of bulk materials; this splitting actually br ...

Nature Portfolio2023

How Acid Washing Nickel Foam Substrates Improves the Efficiency of the Alkaline Hydrogen Evolution Reaction

Jan Van Herle, Peter Hugh Middleton, Suhas Nuggehalli Sampathkumar, Thomas Benjamin Ferriday

Nickel foam substrates are frequently utilised as porous 3D substrates for renewable energy applications. The preparation of these substrates usually includes an acid-washing step, but the degree to which this step affects the final electrochemical perform ...

MDPI2023

Functional Ink Formulation for Printing and Coating of Graphene and Other 2D Materials: Challenges and Solutions

Frank Nüesch, Jakob Heier, Sina Abdolhosseinzadeh, Mohammad Jafarpour

The properties of 2D materials are unparalleled when compared to their 3D counterparts; many of these properties are a consequence of their size reduction to only a couple of atomic layers. Metallic, semiconducting, and insulating types can be found and fo ...

WILEY2022

2D MoS2 Nanopores: Wafer-scale Fabrication and Monolayer Stability for Long-term Single-Molecule Sensing

Mukeshchand Thakur

Biologically inspired solid-state nanopores are artificial openings or apertures in thin membranes similar to natural protein ion channels in a lipid bilayer of cell membranes. In solid-state nanopores, a thin insulating membrane with single or multiple po ...

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

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