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Concept

Cristallisation fractionnée (chimie)

Publications associées (24)

The molecular scale mechanism of deposition ice nucleation on silver iodide

Athanasios Nenes, Mária Lbadaoui-Darvas

Heterogeneous ice nucleation is a ubiquitous process in the natural and built environment. Deposition ice nucleation, i.e. heterogeneous ice nucleation that - according to the traditional view - occurs in a subsaturated water vapor environment and in the a ...

Royal Soc Chemistry2024

Crossing the ballistic-ohmic transition via high energy electron irradiation

Philip Johannes Walter Moll, Matthias Carsten Putzke

The delafossite metal PtCoO2 is among the highest-purity materials known, with low-temperature mean free path up to 5 mu m in the best as-grown single crystals. It exhibits a strongly faceted, nearly hexagonal Fermi surface. This property has profound cons ...

AMER PHYSICAL SOC2023

Three-dimensional in situ imaging of single-grain growth in polycrystalline In2O3:Zr films

Quentin Thomas Jeangros, Monica Morales Masis, Michael Elias Stückelberger

Understanding grain morphology and kinetics of solid-phase crystallization is important for controlling the functional properties of polycrystalline materials. Here, in situ coherent X-ray diffraction imaging and transmission electron microscopy elucidate ...

SPRINGERNATURE2022

Bifunctional additive 2-amino-3-hydroxypyridine for stable and high-efficiency tin-lead perovskite solar cells

Mohammad Khaja Nazeeruddin, Yi Zhang, Keith Gregory Brooks, Bing Zhang

Tin-lead (Sn-Pb) mixed perovskite has received widespread attention due to its suitable band gap width and high optical absorption coefficients. However, the power conversion efficiency (PCE) of Sn-Pb mixed perovskite solar cells (PSCs) is still low due to ...

Royal Society of Chemistry2022

A combined molecular dynamics and experimental study of two-step process enabling low-temperature formation of phase-pure α-FAPbI3

Michael Graetzel, Shaik Mohammed Zakeeruddin, Ursula Röthlisberger, Ulf Anders Hagfeldt, Paramvir Ahlawat, Essa Awadh R Alharbi, Haizhou Lu

It is well established that the lack of understanding the crystallization process in a two-step sequential deposition has a direct impact on efficiency, stability, and reproducibility of perovskite solar cells. Here, we try to understand the solid-solid ph ...

2021

Structural properties of organometalic halide perovskite and their application in photodetectors

Anastasiia Glushkova

Hybrid organometallic halide perovskites have been intensively investigated in the past years as highly efficient light harvesters for various optoelectronic applications for both sensing and emitting light. However, many open questions remain regarding th ...

EPFL2020

Entropy as a tool for crystal discovery

Pablo Miguel Piaggi

The computational prediction of crystal structures has emerged as an useful alternative to expensive and often cumbersome experiments. We propose an approach to the prediction of crystal structures and polymorphism based on reproducing the crystallization ...

EPFL2019

Predicting polymorphism in molecular crystals using orientational entropy

Pablo Miguel Piaggi

We introduce a computational method to discover polymorphs in molecular crystals at finite temperature. The method is based on reproducing the crystallization process starting from the liquid and letting the system discover the relevant polymorphs. This id ...

National Academy of Sciences2018

Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes

Kumar Varoon Agrawal, Guangwei He, Deepu Joseph Babu

We report the synthesis of thin, highly intergrown, polycrystalline metal-organic framework (MOF) membranes on a wide range of unmodified porous and non-porous supports (polymer, ceramic, metal, carbon, and graphene). We developed a novel crystallization t ...

JOURNAL OF VISUALIZED EXPERIMENTS2018

From 2D to 3D Characterization of Materials Subjected to Extreme Pressure and Temperature Conditions

Farhang Nabiei

Planetesimal were the first planetary objects to form in the solar system, which later grew to make the proto-planets. Most of these bodies were differentiated as a result of internal heating. Several differentiated bodies have, then, been accreted followi ...

EPFL2017

The Many Faces of Mixed Ion Perovskites: Unraveling and Understanding the Crystallization Process

Mohammad Khaja Nazeeruddin, Kevin Sivula, Jun Ho Yum, Iwan Zimmermann, Paul Gratia

Understanding the crystallization process of organic-inorganic halide perovskites is of paramount importance for fabrication of reproducible and efficient perovskite solar cells. We report for the first time on the discovery and interplay of ubiquitous hex ...

Amer Chemical Soc2017

From Twinning to Pure Zincblende Catalyst-Free InAs(Sb) Nanowires

Anna Fontcuberta i Morral, Gözde Tütüncüoglu, Martin George Friedl, Heidi Andrea Potts, Esther Alarcon Llado, Federico Matteini, Francesca Amaduzzi

III-V nanowires are candidate building blocks for next generation electronic and optoelectronic platforms. Low bandgap semiconductors such as In As and InSb are interesting because of their high electron mobility. Fine control of the structure, morphology, ...

American Chemical Society2016

Liquid phase crystallized silicon on glass: Technology, material quality and back contacted heterojunction solar cells

Jan Haschke

Liquid phase crystallization has emerged as a novel approach to grow large grained polycrystalline silicon films on glass with high electronic quality. In recent years a lot of effort was conducted by different groups to determine and optimize suitable int ...

Iop Publishing Ltd2016

Crystallization of undercooled liquid fenofibrate

Esther Amstad

Formulation of hydrophobic drugs as amorphous materials is highly advantageous as this increases their solubility in water and therefore their bioavailability. However, many drugs have a high propensity to crystallize during production and storage, limitin ...

Royal Society of Chemistry2015

Facile route to freestanding CH3NH3PbI3 crystals using inverse solubility

Michael Graetzel, Ulf Anders Hagfeldt, Kazuteru Nonomura, Jeannette Medina Kadro

CH3NH3PbI3 was found to exhibit inverse solubility at high temperatures in gamma-butyrolactone. Making use of this unusual, so far unreported phenomenon, we present a facile method for the growth of freestanding crystals of CH3NH3PbI3 from solution without ...

Nature Publishing Group2015

Parametric Polytope Reconstruction, an Application to Crystal Shape Estimation

Colin Neil Jones, Jean-Hubert Hours

In situ imaging techniques are a promising direction for monitoring the distribution of crystal sizes and shapes during a crystallization process. Nevertheless, no tractable method yet exists for estimating complex crystal shapes. In this paper, an in situ ...

Institute of Electrical and Electronics Engineers2014

Expansion mechanisms in calcium aluminate and sulfoaluminate systems with calcium sulfate

Karen Scrivener, Christophe Gosselin, Julien Bizzozero

The long-term expansion of calcium aluminate cement and calcium sulfoaluminate cement in the presence of added gypsum has been studied for samples cured under water. Progressively higher amounts of gypsum were added to the CAC or CSA and it was found that ...

Pergamon-Elsevier Science Ltd2014

Hydration and dimensional stability of calcium aluminate cement based systems

Julien Bizzozero

Calcium aluminate cements (CAC) are often used in combination with calcium sulfate and Portland cement for special applications where rapid setting, rapid drying and shrinkage compensation are required. A growing fraction of the clinker, which has the high ...

EPFL2014

Mechanism of expansion of mortars immersed in sodium sulfate solutions

Wei Sun, Karen Scrivener

The mechanisms behind the expansion of samples immersed in solutions containing sulfate ions have been controversial. Expansion is believed to originate in the formation of ettringite, but it is not possible to find any direct correlation between these two ...

Pergamon-Elsevier Science Ltd2013

Advanced divertor configurations with large flux expansion

Basil Duval, Stefano Coda, Holger Reimerdes, Benoît Labit, Mario Ludovico Podesta, Wouter Vijvers

Experimental studies of the novel snowflake divertor concept (D. Ryutov, Phys. Plasmas 14 (2007) 064502) performed in the NSTX and TCV tokamaks are reviewed in this paper. The snowflake divertor enables power sharing between divertor strike points, as well ...

Elsevier Science Bv2013