Publications related to Particle size

Effects of Hyporheic Exchange and Settlement on the Particle Size Distribution of Colloids

Colloid particle size plays an important role in contaminant adsorption and clogging in the hyporheic zone, but it remains unclear how the particle size changes during the transport of colloids. This study investigated the variation of the particle size of ...

Springer2024

Second harmonic scattering of nanoparticles: A journey into the electrical double layer

Bingxin Chu

In aqueous solutions, a charged surface causes the redistribution of nearby ions. The ion layers formed are known as the electrical double layer (EDL), and are widespread in many systems involving electrochemistry, colloidal science, biomedicine, and energ ...

EPFL2024

Influence of Sphericity on Surface Termination of Icosahedral Colloidal Clusters

Esther Amstad

Colloids self-organize into icosahedral clusters composed of a Mackay core and an anti-Mackay shell under spherical confinement to minimize the free energy. This study explores the variation of surface arrangements of colloids in icosahedral clusters, focu ...

Wiley-V C H Verlag Gmbh2023

Optical manipulation of plasmonic nanoparticles: Applications in surface chemistry and nano-optics

Jeonghyeon Kim

Optical tweezers are devices that can manipulate nano- and microparticles using a laser. The principle of optical tweezers is to apply a force to an object using the momentum of light. This force is very small, but it is sufficient to move things in the mi ...

EPFL2023

Dynamic Nuclear Polarization of Inorganic Halide Perovskites

David Lyndon Emsley, Dominik Józef Kubicki, Gabriele Stevanato, Michael Allan Hope, Aditya Mishra

The intrinsic low sensitivity of nuclear magnetic resonance (NMR) experiments limits their utility for structure determination of materials. Dynamic nuclear polarization (DNP) under magic angle spinning (MAS) has shown tremendous potential to overcome this ...

2023

Size dependence of second-harmonic scattering from nanoparticles: Disentangling surface and electrostatic contributions

Sylvie Roke, Arianna Marchioro, Bingxin Chu

Polarimetric angle-resolved second-harmonic scattering (AR-SHS) is an all-optical tool enabling the study of unlabeled interfaces of nano-sized particles in an aqueous solution. As the second harmonic signal is modulated by interference between nonlinear c ...

AIP Publishing2023

Hydrogel-Encased Photonic Microspheres with Enhanced Color Saturation and High Suspension Stability

Esther Amstad

Regular arrays of colloidal particles can produce striking structural colors without the need for any chemical pigments. Regular arrays of colloidal particles can be processed into microparticles via emulsion templates for use as structural colorants. Phot ...

Amer Chemical Soc2023

Low and high frequency electromagnetic forces: numerical modelling and practical applications

Marco Riccardi

The understanding and manipulation of nanoscale analytes is a central theme in nanotechnology and has been one of the main driving forces behind the development of this field as we know it today. Furthermore, such a technology has the potential to also rev ...

EPFL2022

High-frequency gaseous and particulate chemical characterization using extractive electrospray ionization mass spectrometry (Dual-Phase-EESI-TOF)

Andrea Baccarini, Imad El Haddad, Mihnea Surdu, Houssni Lamkaddam

To elucidate the sources and chemical reaction pathways of organic vapors and particulate matter in the ambient atmosphere, real-time detection of both the gas and particle phase is needed. State-of-the-art techniques often suffer from thermal decompositio ...

COPERNICUS GESELLSCHAFT MBH2022

Simulating Microswimmers Under Confinement With Dissipative Particle (Hydro) Dynamics

Ignacio Pagonabarraga Mora

In this work we study microwimmers, whether colloids or polymers, embedded in bulk or in confinement. We explicitly consider hydrodynamic interactions and simulate the swimmers via an implementation inspired by the squirmer model. Concerning the surroundin ...

FRONTIERS MEDIA SA2022

Engineering Absorption for Foil Applications

Sebastian Mader

Light matter interactions such as extinction, reflection, and transmission can be described by classical optics. Dur-ing the past decades, research focused on a novel resonant extinction type called plasmonics that allows for en-hancement of both types of ...

EPFL2022

Colloidal Nanocrystals as Precursors and Intermediates in Solid State Reactions for Multinary Oxide Nanomaterials

Raffaella Buonsanti, Anna Loiudice, Valeria Mantella

Polyelemental compounds with dimensions in the nanosized regime are desirable in a large variety of applications, yet their synthesis remains a general challenge in chemistry. One of the major bottlenecks to obtaining multinary systems is the complexity of ...

2021

Mechanistic Study on Thermally Induced Lattice Stiffening of ZIF-8

Wendy Lee Queen, Kumar Varoon Agrawal, Pascal Alexander Schouwink, Jian Hao, Mehrdad Asgari, Deepu Joseph Babu, Qi Liu

The flexibility of the ZIF-8 aperture, which inhibits a molecular cutoff of 3.4 angstrom, can be reduced by rapid heat treatment to obtain CO2-selective membranes. However, the early stages of the structural, morphological, and chemical changes responsible ...

2021

Surfactants Control Optical Trapping near a Glass Wall

Olivier Martin, Jeonghyeon Kim

Beyond their original capability to grab and hold tiny objects, optical tweezers have emerged as a powerful tool to investigate fundamental physics at microscopic scales. A precise characterization of the optical trap is one of the key requirements in such ...

AMER CHEMICAL SOC2022

An Experimental Setup for Heterogeneous Catalysis on Atomically Defined Metal Nanostructures

Jean-Guillaume De Groot

The main objective of this PhD thesis is to link the atomic scale structure to the catalytic properties of self-assembled nanostructures. The growth and characterization of these nanostructures was carried out in an ultra-high vacuum (UHV) chamber initiall ...

EPFL2021

Developing the Chemistry of Colloidal Cu Nanocrystals to Advance the CO2 Electrochemical Reduction

Raffaella Buonsanti

The ability to tailor make materials with atomic scale precision is crucial for understanding the sensitivities of their performance parameters and for achieving the design specification corresponding to optimal device operation. Herein, this topic is disc ...

SWISS CHEMICAL SOC2021

Thermal stability of size-selected copper nanoparticles: Effect of size, support and CO2 hydrogenation atmosphere

Andreas Züttel, Wen Luo, Mostapha Dakhchoune, Kun Zhao, Mo Li, Alexandre Borsay

Metal nanoparticles with a precisely controlled particle size distribution are ideal model catalysts for fundamental studies in catalysis. In this work, the thermal stability of size-selected Cu nanoparticles (Cu NPs) were deposited by magnetron sputtering ...

2020

Three-dimensional electrodes for dielectrophoretic applications

Kevin Keim

This thesis reports the use of metal-coated three-dimensional SU-8 electrodes for dielectrophoretic bio sensing and particle manipulation applications. Placing free standing three-dimensional electrodes in microfluidic channels, electric fields can be appl ...

EPFL2020

The interfacial structure of nano-and micron-sized oil and water droplets stabilized with SDS and Span80

Sylvie Roke, Esther Amstad, Nikolay Smolentsev, Evangelia Zdrali, Gianluca Nicolas Etienne

In this work, we provide a comparison between the stability and the interfacial structure of micrometer-sized and nanometer-sized droplets by employing a multi-instrumental approach comprised of the surface-sensitive technique of sum frequency scattering a ...

2019

Molecular Level Interfacial Studies of Nanoemulsions: Surface Structure, Specific Ion Effects and Stability

Evangelia Zdrali

This thesis is a study on the molecular structure of the interface of nanometer-sized oil droplets dispersed in water, a system known as oil-in-water nanoemulsion. The motivation for this research is the large significance of the interfacial nanostructures ...

EPFL2019