Publications associées à Tuning the deposition of molecular graphene nanoribbons by surface functionalization

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

Micropreparative Gel Electrophoresis for Purification of Nanoscale Bioconjugates

Vitalijs Zubkovs, Ardemis Anoush Boghossian, Sayyed Hashem Sajjadi, Shang-Jung Wu, Yahya Rabbani

Conventional techniques for purifying macromolecular conjugates often require complex and costly installments that are inaccessible to most laboratories. In this work, we develop a one-step micropreparative method based on a trilayered polyacrylamide gel e ...

2024

Nanolithography of the nanocorral structure of chemisorbed oxygen atoms on the graphitic lattice

Kumar Varoon Agrawal, Shaoxian Li

Controlled atomic patterning is an attractive tool to fine tune properties of graphitic lattice. Several O-functionalized derivatives of graphitic lattice have been widely studied, e.g., graphene oxide, reduced graphene oxide, and functionalized carbon nan ...

Pergamon-Elsevier Science Ltd2024

Resonant Tip-Enhanced Raman Spectroscopy of a Single-Molecule Kondo System

Jiri Dolezal

Tip-enhanced Raman spectroscopy (TERS) under ultrahigh vacuum and cryogenic conditions enables exploration of the relations between the adsorption geometry, electronic state, and vibrational fingerprints of individual molecules. TERS capability of reflecti ...

Amer Chemical Soc2024

Imaging and controlling coherent phonon wave packets in single graphene nanoribbons

Klaus Kern, Yang Luo

The motion of atoms is at the heart of any chemical or structural transformation in molecules and materials. Upon activation of this motion by an external source, several (usually many) vibrational modes can be coherently coupled, thus facilitating the che ...

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

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

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

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

Additive Fabrication of Microsupercapacitors

Amin Hodaei

Microsupercapacitors (with footprints from -mm up to -cm scale) have attracted attention for use as electrochemical energy storage devices to power wearables, IoT, and other small microsystems due to their high power density, excellent charge/discharge rev ...

EPFL2023

Full Solution Process of a Near-Infrared Light-Emitting Electrochemical Cell Based on Novel Emissive Ruthenium Complexes of 1,10-Phenanthroline-Derived Ligands and a Eutectic Alloy as the Top Electrode

Mohammad Khaja Nazeeruddin

Near-infrared luminescent materials have recently received considerable attention for a large number of applications, including in solid-state lighting, as bioimaging agents, as photovoltaic cells, and in the telecommunication industry. By adding diverse e ...

AMER CHEMICAL SOC2023

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

Cost Effective Synthesis of Graphene Nanomaterials for Non-Enzymatic Electrochemical Sensors for Glucose: A Comprehensive Review

Theodoros Damartzis

The high conductivity of graphene material (or its derivatives) and its very large surface area enhance the direct electron transfer, improving non-enzymatic electrochemical sensors sensitivity and its other characteristics. The offered large pores facilit ...

MDPI2022

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

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

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

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

Long Spin Lifetime in Rare-Earth Single-Atom Magnets at Surfaces

Boris Sorokin

Further miniaturisation of magnetic storage devices requires an advent of new types of magnets, since classical ferromagnetic materials show lack of remanence at nano- and subnanoscale. A single atom can represent the smallest possible bit of information. ...

EPFL2022

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

Rohit Karnik, Luc Sébastien Bondaz

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

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

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

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