Publications related to Crystallization

Flash Melting Amorphous Ice

Marcel Drabbels, Ulrich Lorenz, Constantin Richard Krüger, Gabriele Bongiovanni, Nathan Junior Mowry

Water can be vitrified if it is cooled at high rates, which makes it possible to outrun crystallization in so-called no man’s land, a range of deeply supercooled temperatures where water crystallizes rapidly. Here, we study the reverse process in pure wate ...

2024

Shaped Laser Pulses for Microsecond Time-Resolved Cryo-EM: Outrunning Crystallization during Flash Melting

Marcel Drabbels, Ulrich Lorenz, Constantin Richard Krüger, Nathan Junior Mowry

Water vitrifies if cooled at rates above 3 × 105 K/s. In contrast, when the resulting amorphous ice is flash heated, crystallization occurs even at a more than 10 times higher heating rate, as we have recently shown. This may present an issue for microseco ...

2024

The molecular scale mechanism of deposition ice nucleation on silver iodide

Athanasios Nenes, Mária Lbadaoui-Darvas, André Welti

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

Influence of ionization and cumulative effects on laser-induced crystallization in multilayer dielectrics

Yves Bellouard, Victor Carle Adrien Boureau, Ruben Ricca

Crystallization of amorphous layers has been demonstrated under various radically different laser-exposure conditions, including continuous wave (cw) and pulsed lasers. Here, we investigate the specific role of ionization in the crystallization of dielectr ...

2024

Crystallization of FAPbI3: Polytypes and stacking faults

Paramvir Ahlawat

Molecular dynamics simulations are performed to study the crystallization of formamidinium lead iodide. From all-atom simulations of the crystal growth process and the delta-alpha-phase transitions, we try to reveal the formation of various stack-faulted i ...

Aip Publishing2023

Controlling the crystal structure of succinic acid via microfluidic spray-drying

Esther Amstad, Aysu Ceren Okur

Many properties of materials, including their dissolution kinetics, hardness, and optical appearance, depend on their structure. Unfortunately, it is often difficult to control the structure of low molecular weight organic compounds that have a high propen ...

ROYAL SOC CHEMISTRY2023

RaFSIP: Parameterizing ice multiplication in models using a machine learning approach

Athanasios Nenes, Paraskevi Georgakaki

Accurately representing mixed-phase clouds (MPCs) in global climate models (GCMs) is critical for capturing climate sensitivity and Arctic amplification. Secondary ice production (SIP), can significantly increase ice crystal number concentration (ICNC) in ...

2024

Spin dynamics, loop formation and cooperative reversal in artificial quasicrystals with tailored exchange coupling

Dirk Grundler, Sho Watanabe, Vinayak Shantaram Bhat

Aperiodicity and un-conventional rotational symmetries allow quasicrystalline structures to exhibit unusual physical and functional properties. In magnetism, artificial ferromagnetic quasicrystals exhibited knee anomalies suggesting reprogrammable magnetic ...

2023

Oriented nucleation in formamidinium perovskite for photovoltaics

Mohammad Khaja Nazeeruddin, Paul Joseph Dyson, Yong Ding, Bin Ding, Yang Yang, Xu Zhang, Ke Zhao

The black phase of formamidinium lead iodide (FAPbI(3)) perovskite shows huge promise as an efficient photovoltaic, but it is not favoured energetically at room temperature, meaning that the undesirable yellow phases are always present alongside it during ...

NATURE PORTFOLIO2023

Iodine oxoacids enhance nucleation of sulfuric acid particles in the atmosphere

Andrea Baccarini, Imad El Haddad, Mihnea Surdu, Lubna Dada, André Welti, Houssni Lamkaddam

The main nucleating vapor in the atmosphere is thought to be sulfuric acid (H2SO4), stabilized by ammonia (NH3). However, in marine and polar regions, NH3 is generally low, and H2SO4 is frequently found together with iodine oxoacids [HIOx, i.e., iodic acid ...

American Association for the Advancement of Science2023

Characteristic rupture height of the mediating air film beneath an impacting drop on atomically smooth mica

John Martin Kolinski, Ramin Kaviani

Before a droplet can contact a surface during impact, it must first displace the air beneath it. Over a wide range of impact velocities, the droplet first squeezes the air into a thin film, enhancing its resistance to drainage; this slows the progress of t ...

Amer Physical Soc2023

Microfluidic study in a meter-long reactive path reveals how the medium’s structural heterogeneity shapes MICP-induced biocementation

Lyesse Laloui, Dimitrios Terzis, Ariadni Elmaloglou

Microbially induced calcium carbonate (CaCO3) precipitation (MICP) is one of the major sustainable alternatives to the artificial cementation of granular media. MICP consists of injecting the soil with bacterial- and calcium-rich solutions sequentially to ...

Nature Research2022

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

Electron diffraction of deeply supercooled water in no man’s land

Marcel Drabbels, Ulrich Lorenz, Constantin Richard Krüger, Gabriele Bongiovanni, Nathan Junior Mowry

A generally accepted understanding of the anomalous properties of water will only emerge if it becomes possible to systematically characterize water in the deeply supercooled regime, from where the anomalies appear to emanate. This has largely remained elu ...

Nature Research2023

Site-selective overgrowth of Ag nanocrystals by Polyvinylpyrrolidone-mediated atom deposition by Ostwald ripening

Francesco Stellacci, Paulo Henrique Jacob Silva, Alejandro Lapresta Fernandez

The growth modulation of metal nanocrystals (NCs) by Ostwald ripening (OR) involves control of the relocation of matter by diffusional mass transfer from the dissolution of small nanocrystals (SNCs) towards large nanocrystals whose surface energy is lower. ...

ELSEVIER2022

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

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

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

Investigation in Crystal Growth/Morphology and Interface Engineering of Perovskite Solar Cells by Different Deposition Methods

Nadja Isabelle Desiree Klipfel

A new and promising technology has emerged to compete with traditional silicon photovoltaic semiconductors. The low material and processing costs and high-power conversion efficiencies of organic-inorganic metal halide perovskites make these a promising te ...

EPFL2022

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

Additive Manufacturing of Bulk Metallic Glasses-Process, Challenges and Properties: A Review

Roland Logé, Jamasp Jhabvala, Navid Sohrabi

Bulk Metallic Glasses (BMG) are metallic alloys that have the ability to solidify in an amorphous state. BMGs show enhanced properties, for instance, high hardness, strength, and excellent corrosion and wear resistance. BMGs produced by conventional method ...

MDPI2021

Critical crystallization properties of an industrial-grade Zr-based metallic glass used in additive manufacturing

Roland Logé, Jamasp Jhabvala, Navid Sohrabi

The major challenge to overcome when processing metallic glasses (MGs) is to avoid crystallization. Therefore, time-temperature-transformation (TTT) diagrams are used, but they are often derived from experiments in which heating or cooling rates are limite ...

2021