Publications associées à Électrophorèse

Surface Charge Boundary Condition Often Misused in CO2 Reduction Models

Sophia Haussener, Etienne Boutin, Evan Fair Johnson

The Poisson-Nernst-Planck equations have been used to model species transport in electrochemical CO2 reduction, where the surface charge boundary condition accounts for the potential drop across the Stern layer. A direct comparison of the published models ...

AMER CHEMICAL SOC2023

Electrokinetic, electrochemical, and electrostatic surface potentials of the pristine water liquid-vapor interface

Philip Robin Loche

Although conceptually simple, the air-water interface displays rich behavior and is subject to intense experimental and theoretical investigations. Different definitions of the electrostatic surface potential as well as different calculation methods, each ...

AIP Publishing2022

Self-Propulsion of Active Colloids via Ion Release: Theory and Experiments

Ignacio Pagonabarraga Mora, Samuel Sanchez

We study the self-propulsion of a charged colloidal particle that releases ionic species using theory and experiments. We relax the assumptions of thin Debye length and weak nonequilibrium effects assumed in classical phoretic models. This leads to a numbe ...

2020

Electrosorption at metal surfaces from first principles

Nicola Marzari

Electrosorption of solvated species at metal electrodes is a most fundamental class of processes in interfacial electrochemistry. Here, we use its sensitive dependence on the electric double layer to assess the performance of ab initio thermodynamics appro ...

NATURE PUBLISHING GROUP2020

How to polarise an interface with ions: the discrete Helmholtz model

Hubert Girault, Astrid Johana Olaya Avendano, Grégoire Clément Gschwend

The distribution of electrolytes in an electric field usually relies on theories based on the Poisson-Boltzmann formalism. These models predict that, in the case of a metallic electrode, ionic charges screen the electrode potential, leading to concentratio ...

2020

Photoemission from non-polar aromatic molecules in the gas and liquid phase

Majed Chergui, Frank van Mourik, Christopher Alexander Arrell, Lars-Hendrik Mewes, José Javier Pancracio Ojeda Andara, Jakob Grilj, Luca Longetti

The photoelectron spectra of both liquid and gas phase aromatic molecules are reported. The spectra were obtained using a 34.1 eV source produced by high harmonic generation and analysed with the help of high-level ab initio simulations using the reflectio ...

ROYAL SOC CHEMISTRY2020

On‐chip technology for single‐cell arraying, electrorotation‐based analysis and selective release

Carlotta Guiducci, Samuel Kilchenmann, Kevin Keim, Paul Karoly Otto Ery, Mohamed Zakarya Alsaid Ali Rashed

This paper reports a method for label-free single-cell biophysical analysis of multiple cells trapped in suspension by electrokinetic forces. Tri-dimensional pillar electrodes arranged along the width of a microfluidic chamber define actuators for single c ...

2019

Specific Ion Effects at the Interface of Nanometer-Sized Droplets in Water: Structure and Stability

Sylvie Roke, Halil Ibrahim Okur, Evangelia Zdrali

The interaction of ions with interfaces influences numerous processes in chemistry, physics, and biology, while different ion species behave differently at hydrophobic or hydrophilic interfaces. Despite its importance, ion specificity and its relation to s ...

2019

Detecting topological variations of DNA at single-molecule level

Aleksandra Radenovic, Georg Fantner, Adrian Pascal Nievergelt, Ke Liu

In addition to their use in DNA sequencing, ultrathin nanopore membranes have potential applications in detecting topological variations in deoxyribonucleic acid (DNA). This is due to the fact that when topologically edited DNA molecules, driven by electro ...

Nature Research2019

Physical vapour deposition of cyanine salts and their first application in organic electronic devices

Frank Nüesch, Jakob Heier, Antonia Neels, Léo Duchêne, Donatas Gesevicius

A symmetrical trimethine indocyanine dye chromophore was modified with the bistriflylimide anion to study the changes in Coulomb interactions, thermal stability and the volatility of the organic salt. The bulky bistriflylimide anion minimizes electrostatic ...

Royal Society of Chemistry2019

Two dimensional diffusion-controlled triplet–triplet annihilation kinetics

Hubert Girault, Astrid Johana Olaya Avendano, Pierre-François Marie Brevet, Grégoire Clément Gschwend, Morgan Kazmierczak

Diffusion controlled chemical reactions are usually observed in three dimensionalmedia. In contrast, planar bimolecular reactions taking place between reagents adsorbed at a soft interface are two-dimensional and therefore cannot be studied within the same ...

2019

Superweak Coordinating Anion as Superstrong Enhancer of Cyanine Organic Semiconductor Properties

Frank Nüesch, Jakob Heier, Antonia Neels, Donatas Gesevicius

The superweak tetrakis(nonafluoro-tert-butoxy)aluminate coordinating anion was employed to introduce pseudo-gas-phase conditions to the 2-[5-(1,3-dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)-1,3-pentadien-1-yl]-1,3,3-trimethyl-3H-indolium chromophore. The r ...

2018

Nanoplasmonic mid-infrared biosensor for in vitro protein secondary structure detection

Giovanni Dietler, Hilal Lashuel, Hatice Altug, Dordaneh Etezadi, Francesco Simone Ruggeri, John Blaine Warner IV

Plasmonic nanoantennas offer new applications in mid-infrared (mid-IR) absorption spectroscopy with ultrasensitive detection of structural signatures of biomolecules, such as proteins, due to their strong resonant near-fields. The amide I fingerprint of a ...

Springer Nature2017

Optical label-free and model-free probe of the surface potential of nanoscale and microscopic objects in aqueous solution

Sylvie Roke, Cornelis Ulrich Lütgebaucks

The electrostatic environment of aqueous systems is an essential ingredient for the function of any living system. To understand the electrostatic properties and their molecular foundation in soft, living, and three-dimensional systems, we developed a tabl ...

Amer Physical Soc2016

Hematite photoelectrodes for water splitting: evaluation of the role of film thickness by impedance spectroscopy

Michael Graetzel, Kevin Sivula, Florian Le Formal

The electrochemical behavior of alpha-Fe2O3 photoelectrodes prepared by spray pyrolysis with different thicknesses was examined under dark and illumination conditions. The main charge transport phenomena occurring in the PEC cell photoelectrodes were chara ...

Royal Soc Chemistry2014

Measurement of the Position-Dependent Electrophoretic Force on DNA in a Glass Nanocapillary

Aleksandra Radenovic, Lorenz Jan Steinbock, Roman Bulushev, Sergey Khlybov

The electrophoretic force on a single DNA molecule inside a glass nanocapillary depends on the opening size and varies with the distance along the symmetrical axis of the nanocapillary. Using optical tweezers and DNA-coated beads, we measured the stalling ...

American Chemical Society2014

Colloidal Stability of Self-Assembled Mono layer-Coated Gold Nanoparticles: The Effects of Surface Compositional and Structural Heterogeneity

Francesco Stellacci, Randy Patrick Carney

Surface heterogeneity plays an important role in controlling colloidal phenomena. This study investigated the self-aggregation and bacterial adsorption of self-assembled monolayer coated gold nanoparticles (AuNPs) with different surface compositional and s ...

American Chemical Society2013

Differential capacitance of liquid/liquid interfaces of finite thicknesses: a finite element study

Hubert Girault, Dmitry Momotenko, Carlos Manuel De Melo Pereira

Finite element simulations were used to investigate the effect of a smooth variation of permittivity across a polarized liquid/liquid interface on the differential capacitance. The results show that a relative permittivity profile can account for the varia ...

Royal Soc Chemistry2012

Segmented Field OFFGEL® Electrophoresis

Hubert Girault, Julien Maillard, Fernando Cortes Salazar, Dmitry Momotenko, Elena Tobolkina

A multielectrode setup for protein OFFGEL electrophoresis that significantly improves protein separation efficiency has been developed. Here, the electric field is applied by segments between seven electrodes connected in series to six independent power su ...

Wiley-Blackwell2012

Dielectrophoresis-based continuous-flow particle microreactor

Raphaël Tornay

This thesis mainly deals with the integration of a microfluidic system for the extraction of micrometric and submicrometric particles from a solution. Traditional methods take from several minutes to hours to separate particles from a solution. Microfluidi ...

EPFL2009