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Lorenz N, Wittenberg C, Palberg T. Porous crystals in charged sphere suspensions by aggregate-driven phase separation. SOFT MATTER 2023. [PMID: 37367202 DOI: 10.1039/d3sm00660c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
The kinetics of phase transition processes often governs the resulting material microstructure. Using optical microscopy, we here investigate the formation and stabilization of a porous crystalline microstructure forming in low-salt suspensions of charged colloidal spheres containing aggregates comprising some 5-10 of these colloids. We observe the transformation of an initially crystalline colloidal solid with homogeneously incorporated aggregates to individual, compositionally refined crystallites of perforated morphology coexisting with an aggregate-enriched fluid phase filling the holes and separating individual crystallites. A preliminary kinetic characterization suggests that the involved processes follow power laws. We show that this route to porous materials is neither restricted to nominally single component systems nor to a particular microstructure to start from. However, it necessitates an early rapid solidification stage during which the aggregates become trapped in the bulk of the host-crystals. The thermodynamic stability of the reconstructed crystalline scaffold against melting under increased salinity was found comparable to that of pure phase crystallites grown very slowly from a melt. Future implications of this novel route to porous colloidal crystals are discussed.
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Affiliation(s)
- Nina Lorenz
- Institute of Physics, Johannes Gutenberg Universität Mainz, Germany.
| | | | - Thomas Palberg
- Institute of Physics, Johannes Gutenberg Universität Mainz, Germany.
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2
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Lorenz N, Gupta I, Palberg T. Microstructural diversity, nucleation paths, and phase behavior in binary mixtures of charged colloidal spheres. J Chem Phys 2023; 158:114902. [PMID: 36948792 DOI: 10.1063/5.0140949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/17/2023] Open
Abstract
We study low-salt, binary aqueous suspensions of charged colloidal spheres of size ratio Γ = 0.57, number densities below the eutectic number density nE, and number fractions of p = 1.00-0.40. The typical phase obtained by solidification from a homogeneous shear-melt is a substitutional alloy with a body centered cubic structure. In strictly gas-tight vials, the polycrystalline solid is stable against melting and further phase transformation for extended times. For comparison, we also prepare the same samples by slow, mechanically undisturbed deionization in commercial slit cells. These cells feature a complex but well reproducible sequence of global and local gradients in salt concentration, number density, and composition as induced by successive deionization, phoretic transport, and differential settling of the components, respectively. Moreover, they provide an extended bottom surface suitable for heterogeneous nucleation of the β-phase. We give a detailed qualitative characterization of the crystallization processes using imaging and optical microscopy. By contrast to the bulk samples, the initial alloy formation is not volume-filling, and we now observe also α- and β-phases with low solubility of the odd component. In addition to the initial homogeneous nucleation route, the interplay of gradients opens various further crystallization and transformation pathways leading to a great diversity of microstructures. Upon a subsequent increase in salt concentration, the crystals melt again. Wall-based, pebble-shaped β-phase crystals and facetted α-crystals melt last. Our observations suggest that the substitutional alloys formed in bulk experiments by homogeneous nucleation and subsequent growth are mechanically stable in the absence of solid-fluid interfaces but thermodynamically metastable.
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Affiliation(s)
- Nina Lorenz
- Institute of Physics, Johannes Gutenberg University, 55122 Mainz, Germany
| | - Ishan Gupta
- Graz University of Technology, Institute of Applied Mechanics, Graz, Austria
| | - Thomas Palberg
- Institute of Physics, Johannes Gutenberg University, 55122 Mainz, Germany
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3
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Yuan J, Takae K, Tanaka H. Impact of Inverse Squeezing Flow on the Self-Assembly of Oppositely Charged Colloidal Particles under Electric Field. PHYSICAL REVIEW LETTERS 2022; 129:248001. [PMID: 36563242 DOI: 10.1103/physrevlett.129.248001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 11/15/2022] [Indexed: 06/17/2023]
Abstract
Hydrodynamic interactions (HIs) play a critical role in the self-organization of colloidal suspensions and biological solutions. However, their roles have remained elusive particularly for charged soft matter systems. Here we consider the role of HIs in the self-assembly of oppositely charged colloidal particles, which is a promising candidate for electrical tunable soft materials. We employ the fluid particle dynamics method to consider many-body HIs and the coupling between the colloid, ion, and fluid motions. We find that, under a constant electric field, oppositely charged colloidal particles form clusters and percolate into a gel network, unlike bundlelike aggregates aligned in the field direction observed by Brownian dynamics simulations neglecting HIs. We reveal that the cluster-forming tendency originates from the incompressibility-induced "inverse squeezing flow" effect that dramatically slows down the disaggregation of attached colloids. Our findings indicate that the HI selects a unique kinetic pathway to the nonequilibrium colloidal self-assembly.
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Affiliation(s)
- Jiaxing Yuan
- Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
| | - Kyohei Takae
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
| | - Hajime Tanaka
- Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8904, Japan
- Department of Fundamental Engineering, Institute of Industrial Science, University of Tokyo, 4-6-1 Komaba, Meguro-ku, Tokyo 153-8505, Japan
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4
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Self-assembly in binary mixtures of spherical colloids. Adv Colloid Interface Sci 2022; 308:102748. [DOI: 10.1016/j.cis.2022.102748] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2022] [Revised: 06/16/2022] [Accepted: 07/29/2022] [Indexed: 11/18/2022]
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5
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LaCour RA, Moore TC, Glotzer SC. Tuning Stoichiometry to Promote Formation of Binary Colloidal Superlattices. PHYSICAL REVIEW LETTERS 2022; 128:188001. [PMID: 35594109 DOI: 10.1103/physrevlett.128.188001] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 03/27/2022] [Accepted: 03/31/2022] [Indexed: 06/15/2023]
Abstract
The self-assembly of binary nanoparticle superlattices from colloidal mixtures is a promising method for the fabrication of complex colloidal cocrystal structures. However, binary mixtures often form amorphous or metastable phases instead of the thermodynamically stable phase. Here we show that in binary mixtures of differently sized spherical particles, an excess of the smaller component can promote-and, in some cases, may be necessary for-the self-assembly of a binary cocrystal. Using computer simulations, we identify two mechanisms responsible for this phenomenon. First, excess small particles act like plasticizers and enable systems to reach a greater supersaturation before kinetic arrest occurs. Second, they can disfavor competing structures that may interfere with the growth of the target structure. We find the phase behavior of simulated mixtures of nearly hard spheres closely matches published experimental results. We demonstrate the generality of our findings for mixtures of particles of arbitrary shape by presenting a binary mixture of hard shapes that only self-assembles with an excess of the smaller component.
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Affiliation(s)
- R Allen LaCour
- Department of Chemical Engineering, The University of Michigan, Ann Arbor, Michigan 48109, USA Biointerfaces Institute, The University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Timothy C Moore
- Department of Chemical Engineering, The University of Michigan, Ann Arbor, Michigan 48109, USA Biointerfaces Institute, The University of Michigan, Ann Arbor, Michigan 48109, USA
| | - Sharon C Glotzer
- Department of Chemical Engineering, The University of Michigan, Ann Arbor, Michigan 48109, USA Biointerfaces Institute, The University of Michigan, Ann Arbor, Michigan 48109, USA
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6
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Schwarz J, Leiderer P, Palberg T. Salt-concentration-dependent nucleation rates in low-metastability colloidal charged sphere melts containing small amounts of doublets. Phys Rev E 2021; 104:064607. [PMID: 35030906 DOI: 10.1103/physreve.104.064607] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 11/29/2021] [Indexed: 06/14/2023]
Abstract
We determined bulk crystal nucleation rates in aqueous suspensions of charged spheres at low metastability. Experiments were performed in dependence on electrolyte concentration and for two different particle number densities. The time-dependent nucleation rate shows a pronounced initial peak, while postsolidification crystal size distributions are skewed towards larger crystallite sizes. At each concentration, the nucleation rate density initially drops exponentially with increasing salt concentration. The full data set, however, shows an unexpected scaling of the nucleation rate densities with metastability times the number density of particles. Parameterization of our results in terms of classical nucleation theory reveals unusually low interfacial free energies of the nucleus surfaces and nucleation barriers well below the thermal energy. We tentatively attribute our observations to the presence of doublets introduced by the employed conditioning technique. We discuss the conditions under which such small seeds may induce nucleation.
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Affiliation(s)
- J Schwarz
- Institute of Physics, Johannes Gutenberg University, 55128 Mainz, Germany
| | - P Leiderer
- Fachbereicht Physik, University of Konstanz, 78457 Konstanz, Germany
| | - T Palberg
- Institute of Physics, Johannes Gutenberg University, 55128 Mainz, Germany
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7
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Anomalous Long-Range Attraction in Colloidal Binary Mixtures at Fluid–Fluid Interfaces. COLLOIDS AND INTERFACES 2020. [DOI: 10.3390/colloids4030036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The properties of binary colloidal systems have gained the interest of researchers because they have much richer structures than their one-component counterpart. Continuing efforts are being made on the theoretical side on binary colloidal systems, while many issues remained unsolved for the lack of solid experimental supports, especially for study in the field of two-dimensional (2D) binary colloids system. Oil–water interfaces can serve as a good stringent 2D confinement for colloidal particles and can avoid anomalous problems caused by the quasi-two-dimensional environment in previous experimental reports. In this work, we conduct experimental research of binary colloids system in an oil–water interface to revisit theoretical predication. We measure an ultra-long-range attraction and discuss the possible mechanism of this attraction by comparing the experimental result with existing model and theory. This study could contribute more understanding of the binary colloidal system in both experimental aspects and theoretical aspects.
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8
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LaCour RA, Adorf CS, Dshemuchadse J, Glotzer SC. Influence of Softness on the Stability of Binary Colloidal Crystals. ACS NANO 2019; 13:13829-13842. [PMID: 31692332 DOI: 10.1021/acsnano.9b04274] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Mixtures of two types of nanoparticles can self-assemble into a wide variety of binary colloidal crystals (also called binary nanoparticle superlattices), which are interesting for their structural diversity and potential applications. Although so-called packing models-which usually treat the particles as "hard" with only excluded volume interactions-seem to explain many reported dense crystalline phases, these models often fail to predict the right structure. Here, we examine the role of soft repulsive interparticle interactions on binary colloidal crystals comprising two sizes of spherical particles; such "softness" can arise due to ligand shells or screened electrostatics. We determine the ground state phase diagram of binary systems of particles interacting with an additive inverse power law potential using a basin hopping algorithm to calculate the enthalpy of an extremely large pool of candidate structures. We find that a surprisingly small amount of softness can destabilize dense packings in favor of less densely packed structures, which provides further evidence that considerations beyond packing are necessary for describing many of the observed phases of binary colloidal crystals. Importantly, we find that several of the phases stabilized by softness, which are characterized by relatively few interparticle contacts and a tendency for local icosahedral order, are more likely to be observed experimentally than those predicted by packing models. We also report a previously unknown dense AB4 phase and conduct free energy calculations to examine how the stability of several crystals will vary with temperature. Our results further our understanding of why particular binary colloidal crystals form and will be useful as a reference for experimentalists working with softly repulsive colloids.
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9
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Niu R, Heidt S, Sreij R, Dekker RI, Hofmann M, Palberg T. Formation of a transient amorphous solid in low density aqueous charged sphere suspensions. Sci Rep 2017; 7:17044. [PMID: 29213089 PMCID: PMC5719089 DOI: 10.1038/s41598-017-17106-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 11/22/2017] [Indexed: 11/09/2022] Open
Abstract
Colloidal glasses formed from hard spheres, nearly hard spheres, ellipsoids and platelets or their attractive variants, have been studied in great detail. Complementing and constraining theoretical approaches and simulations, the many different types of model systems have significantly advanced our understanding of the glass transition in general. Despite their early prediction, however, no experimental charged sphere glasses have been found at low density, where the competing process of crystallization prevails. We here report the formation of a transient amorphous solid formed from charged polymer spheres suspended in thoroughly deionized water at volume fractions of 0.0002-0.01. From optical experiments, we observe the presence of short-range order and an enhanced shear rigidity as compared to the stable polycrystalline solid of body centred cubic structure. On a density dependent time scale of hours to days, the amorphous solid transforms into this stable structure. We further present preliminary dynamic light scattering data showing the evolution of a second slow relaxation process possibly pointing to a dynamic heterogeneity known from other colloidal glasses and gels. We compare our findings to the predicted phase behaviour of charged sphere suspensions and discuss possible mechanisms for the formation of this peculiar type of colloidal glass.
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Affiliation(s)
- Ran Niu
- Institute of Physics, Johannes Gutenberg University, D-55099, Mainz, Germany.
| | - Sabrina Heidt
- Institute of Physics, Johannes Gutenberg University, D-55099, Mainz, Germany
- Graduate School Materials Science in Mainz, Staudinger Weg 9, D-55128, Mainz, Germany
| | - Ramsia Sreij
- Department of Chemistry Physical and Biophysical Chemistry (PC III), Bielefeld University, D-33615, Bielefeld, Germany
| | - Riande I Dekker
- Debye Institute for Nanomaterials Science, Utrecht University, NL-3584 CC, Utrecht, The Netherlands
| | - Maximilian Hofmann
- Institute of Physics, Johannes Gutenberg University, D-55099, Mainz, Germany
| | - Thomas Palberg
- Institute of Physics, Johannes Gutenberg University, D-55099, Mainz, Germany
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10
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Liu J, Shen T, Yang ZH, Zhang S, Sun GY. Multistep Heterogeneous Nucleation in Binary Mixtures of Charged Colloidal Spheres. J Phys Chem Lett 2017; 8:4652-4658. [PMID: 28893063 DOI: 10.1021/acs.jpclett.7b02096] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Nucleation plays a decisive role in determining the crystal structure and size distribution; however, understanding of the fundamentals of nucleation is quite limited. In particular, it is unclear whether a nucleus forms spontaneously from solution via a single- or multiple-step process. Here we show how a binary mixture of charged colloidal spheres nucleates heterogeneously on a flat substrate by means of Bragg microscopy, laser diffraction, and laser microscopy. In contrast with the conventional one-step and two-step nucleation mechanisms, a novel pathway of multistep heterogeneous nucleation under certain experimental conditions is highlighted by four steps: initial homogeneous fluid → prenucleation clusters → preordered prenucleation clusters → intermediate ordered phase → final crystal. It is expected that the obtained results would be helpful in rationalizing the rich phase behavior exhibited by the binary mixture systems and in developing better and broadly applicable nucleation models as well as in designing defect-free single-crystal alloys.
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Affiliation(s)
- Jianing Liu
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
- Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean, Nanjing University of Information Science & Technology , Nanjing 210044, China
| | - Tong Shen
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
- Jiangsu Key Laboratory for Optoelectronic Detection of Atmosphere and Ocean, Nanjing University of Information Science & Technology , Nanjing 210044, China
| | - Zhao Hua Yang
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
| | - Shu Zhang
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
| | - Guang Yu Sun
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology , Nanjing 210044, China
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11
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Herlach DM, Palberg T, Klassen I, Klein S, Kobold R. Overview: Experimental studies of crystal nucleation: Metals and colloids. J Chem Phys 2016; 145:211703. [DOI: 10.1063/1.4963684] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Dieter M. Herlach
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Thomas Palberg
- Institut für Physik, Johannes Gutenberg Universität Mainz, 55099 Mainz, Germany
| | - Ina Klassen
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
- Projektträger Jülich, Forschungszentrum Jülich GmbH, 52425 Jülich, Germany
| | - Stefan Klein
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Raphael Kobold
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
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12
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Finlayson SD, Bartlett P. Non-additivity of pair interactions in charged colloids. J Chem Phys 2016; 145:034905. [DOI: 10.1063/1.4959122] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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13
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Cabane B, Li J, Artzner F, Botet R, Labbez C, Bareigts G, Sztucki M, Goehring L. Hiding in Plain View: Colloidal Self-Assembly from Polydisperse Populations. PHYSICAL REVIEW LETTERS 2016; 116:208001. [PMID: 27258885 DOI: 10.1103/physrevlett.116.208001] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2015] [Indexed: 05/22/2023]
Abstract
We report small-angle x-ray scattering experiments on aqueous dispersions of colloidal silica with a broad monomodal size distribution (polydispersity, 14%; size, 8 nm). Over a range of volume fractions, the silica particles segregate to build first one, then two distinct sets of colloidal crystals. These dispersions thus demonstrate fractional crystallization and multiple-phase (bcc, Laves AB_{2}, liquid) coexistence. Their remarkable ability to build complex crystal structures from a polydisperse population originates from the intermediate-range nature of interparticle forces, and it suggests routes for designing self-assembling colloidal crystals from the bottom up.
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Affiliation(s)
- Bernard Cabane
- LCMD, CNRS UMR 8231, ESPCI, 10 rue Vauquelin, 75231 Paris Cedex 05, France
| | - Joaquim Li
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen, Germany
| | - Franck Artzner
- Institut de Physique de Rennes, CNRS UMR 6251, Université Rennes 1, 35042 Rennes Cedex, France
| | - Robert Botet
- Physique des Solides, CNRS UMR 8502, Université Paris-Sud, F-91405 Orsay, France
| | - Christophe Labbez
- ICB, CNRS UMR 6303, Université de Bourgogne Franche-Comté, F-21078 Dijon, France
| | - Guillaume Bareigts
- ICB, CNRS UMR 6303, Université de Bourgogne Franche-Comté, F-21078 Dijon, France
| | - Michael Sztucki
- ESRF-The European Synchrotron, CS40220, 38043 Grenoble Cedex 9, France
| | - Lucas Goehring
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), 37077 Göttingen, Germany
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14
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Palberg T, Wette P, Herlach DM. Equilibrium fluid-crystal interfacial free energy of bcc-crystallizing aqueous suspensions of polydisperse charged spheres. Phys Rev E 2016; 93:022601. [PMID: 26986371 DOI: 10.1103/physreve.93.022601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2015] [Indexed: 06/05/2023]
Abstract
The interfacial free energy is a central quantity in crystallization from the metastable melt. In suspensions of charged colloidal spheres, nucleation and growth kinetics can be accurately measured from optical experiments. In previous work, from these data effective nonequilibrium values for the interfacial free energy between the emerging bcc nuclei and the adjacent melt in dependence on the chemical potential difference between melt phase and crystal phase were derived using classical nucleation theory (CNT). A strictly linear increase of the interfacial free energy was observed as a function of increased metastability. Here, we further analyze these data for five aqueous suspensions of charged spheres and one binary mixture. We utilize a simple extrapolation scheme and interpret our findings in view of Turnbull's empirical rule. This enables us to present the first systematic experimental estimates for a reduced interfacial free energy, σ(0,bcc), between the bcc-crystal phase and the coexisting equilibrium fluid. Values obtained for σ(0,bcc) are on the order of a few k(B)T. Their values are not correlated to any of the electrostatic interaction parameters but rather show a systematic decrease with increasing size polydispersity and a lower value for the mixture as compared to the pure components. At the same time, σ(0) also shows an approximately linear correlation to the entropy of freezing. The equilibrium interfacial free energy of strictly monodisperse charged spheres may therefore be still greater.
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Affiliation(s)
- Thomas Palberg
- Institut für Physik, Johannes Gutenberg Universität Mainz, 55099 Mainz, Germany
| | - Patrick Wette
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51147 Köln, Germany
- Space Administration, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 53227 Bonn, Germany
| | - Dieter M Herlach
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51147 Köln, Germany
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15
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Beyer R, Franke M, Schöpe HJ, Bartsch E, Palberg T. From nuclei to micro-structure in colloidal crystallization: Investigating intermediate length scales by small angle laser light scattering. J Chem Phys 2015; 143:064903. [DOI: 10.1063/1.4928370] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Richard Beyer
- Institut für Physik, Johannes Gutenberg Universität, D-55099 Mainz, Germany
| | - Markus Franke
- Institut für Physik, Johannes Gutenberg Universität, D-55099 Mainz, Germany
| | | | - Eckhard Bartsch
- Institut für Physikalische Chemie, Albert-Ludwigs-Universität, D-79104 Freiburg, Germany
| | - Thomas Palberg
- Institut für Physik, Johannes Gutenberg Universität, D-55099 Mainz, Germany
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16
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Lash MH, Jordan JC, Blevins LC, Fedorchak MV, Little SR, McCarthy JJ. Non-Brownian Particle-Based Materials with Microscale and Nanoscale Hierarchy. Angew Chem Int Ed Engl 2015. [DOI: 10.1002/ange.201500273] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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17
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Lash MH, Jordan JC, Blevins LC, Fedorchak MV, Little SR, McCarthy JJ. Non-Brownian Particle-Based Materials with Microscale and Nanoscale Hierarchy. Angew Chem Int Ed Engl 2015; 54:5854-8. [DOI: 10.1002/anie.201500273] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2015] [Indexed: 11/12/2022]
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18
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Hornfeck W, Menke D, Forthaus M, Subatzus S, Franke M, Schöpe HJ, Palberg T, Perlich J, Herlach D. Nucleation and crystal growth in a suspension of charged colloidal silica spheres with bi-modal size distribution studied by time-resolved ultra-small-angle X-ray scattering. J Chem Phys 2014; 141:214906. [PMID: 25481168 DOI: 10.1063/1.4902904] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Affiliation(s)
- Wolfgang Hornfeck
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Dirk Menke
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Martin Forthaus
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Sebastian Subatzus
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
| | - Markus Franke
- Institut für Physik, Johannes-Gutenberg-Universität, Staudingerweg 7, 55128 Mainz, Germany
| | - Hans-Joachim Schöpe
- Institut für Physik, Johannes-Gutenberg-Universität, Staudingerweg 7, 55128 Mainz, Germany
| | - Thomas Palberg
- Institut für Physik, Johannes-Gutenberg-Universität, Staudingerweg 7, 55128 Mainz, Germany
| | - Jan Perlich
- Deutsches Elektronensynchrotron (DESY), Notkestr. 85, 22607 Hamburg, Germany
| | - Dieter Herlach
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51170 Köln, Germany
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19
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Palberg T, Maaroufi MR, Stipp A, Schöpe HJ. Micro-structure evolution of wall based crystals after casting of model suspensions as obtained from Bragg microscopy. J Chem Phys 2013; 137:094906. [PMID: 22957593 DOI: 10.1063/1.4749261] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Growth of heterogeneously nucleated, wall based crystals plays a major role in determining the micro-structure during melt casting. This issue is here addressed using a model system of charged colloidal spheres in deionized aqueous suspension observed by Bragg microscopy which is a combination of light scattering and microscopy. We examine the evolution of the three-dimensional size, shape, and orientation of twin domains in monolithic crystals growing from two opposing planar walls into a meta-stable (shear-) melt. At each wall crystal orientation and twinning emerges during nucleation with small domains. During growth these widen and merge. From image analysis we observe the lateral coarsening velocities to follow a power law behaviour L(XY) ∝ t(1/2) as long as the vertical growth continues at constant speed. Lateral coarsening terminates upon intersection of the two solids and hardly any further ripening is seen. Initial lateral coarsening velocities show a Wilson Frenkel type dependence on the melt meta-stability.
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Affiliation(s)
- Thomas Palberg
- University of Mainz, Institute of Physics, Staudingerweg 7, D-55099 Mainz, Germany.
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Löwen H, Allahyarov E, Ivlev A, Morfill GE. Heterogeneous crystallization in colloids and complex plasmas: the role of binary mobilities. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2012; 24:284125. [PMID: 22738924 DOI: 10.1088/0953-8984/24/28/284125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Both charged colloidal suspensions and complex (dusty) plasmas represent classical many-body strongly coupled Coulomb systems. Here we discuss their basic properties and focus on their heterogeneous crystallization from an undercooled melt. In particular, a model with different mobilities is proposed which is realizable in binary mixtures of charged particles. Within this binary-mobility model, the crystallization behaviour near a structured wall is explored by Brownian dynamics computer simulations. As a result, the propagation velocity of the crystal-fluid interface is a nonmonotonic function of the mobility ratio (if expressed in terms of an averaged mobility).
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Affiliation(s)
- H Löwen
- Institut für Theoretische Physik II, Heinrich-Heine-Universität Düsseldorf, 40225 Düsseldorf, Germany.
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Beyer R, Iacopini S, Palberg T, Schöpe HJ. Polymer induced changes of the crystallization scenario in suspensions of hard sphere like microgel particles. J Chem Phys 2012; 136:234906. [DOI: 10.1063/1.4729562] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Colloidal Crystallization Between Two and Three Dimensions. ADVANCES IN CHEMICAL PHYSICS 2011. [DOI: 10.1002/9781118158715.ch3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/28/2023]
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Tóth GI, Tegze G, Pusztai T, Tóth G, Gránásy L. Polymorphism, crystal nucleation and growth in the phase-field crystal model in 2D and 3D. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:364101. [PMID: 21386517 DOI: 10.1088/0953-8984/22/36/364101] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
We apply a simple dynamical density functional theory, the phase-field crystal (PFC) model of overdamped conservative dynamics, to address polymorphism, crystal nucleation, and crystal growth in the diffusion-controlled limit. We refine the phase diagram for 3D, and determine the line free energy in 2D and the height of the nucleation barrier in 2D and 3D for homogeneous and heterogeneous nucleation by solving the respective Euler-Lagrange (EL) equations. We demonstrate that, in the PFC model, the body-centered cubic (bcc), the face-centered cubic (fcc), and the hexagonal close-packed structures (hcp) compete, while the simple cubic structure is unstable, and that phase preference can be tuned by changing the model parameters: close to the critical point the bcc structure is stable, while far from the critical point the fcc prevails, with an hcp stability domain in between. We note that with increasing distance from the critical point the equilibrium shapes vary from the sphere to specific faceted shapes: rhombic dodecahedron (bcc), truncated octahedron (fcc), and hexagonal prism (hcp). Solving the equation of motion of the PFC model supplied with conserved noise, solidification starts with the nucleation of an amorphous precursor phase, into which the stable crystalline phase nucleates. The growth rate is found to be time dependent and anisotropic; this anisotropy depends on the driving force. We show that due to the diffusion-controlled growth mechanism, which is especially relevant for crystal aggregation in colloidal systems, dendritic growth structures evolve in large-scale isothermal single-component PFC simulations. An oscillatory effective pair potential resembling those for model glass formers has been evaluated from structural data of the amorphous phase obtained by instantaneous quenching. Finally, we present results for eutectic solidification in a binary PFC model.
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Affiliation(s)
- Gyula I Tóth
- Research Institute for Solid State Physics and Optics, PO Box 49, H-1525 Budapest, Hungary
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Lorenz NJ, Palberg T. Melting and freezing lines for a mixture of charged colloidal spheres with spindle-type phase diagram. J Chem Phys 2010; 133:104501. [DOI: 10.1063/1.3487523] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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Herlach DM, Klassen I, Wette P, Holland-Moritz D. Colloids as model systems for metals and alloys: a case study of crystallization. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2010; 22:153101. [PMID: 21389545 DOI: 10.1088/0953-8984/22/15/153101] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Metallic systems are widely used as materials in daily human life. Their properties depend very much on the production route. In order to improve the production process and even develop novel materials a detailed knowledge of all physical processes involved in crystallization is mandatory. Atomic systems like metals are characterized by very high relaxation rates, which make direct investigations of crystallization very difficult and in some cases impossible. In contrast, phase transitions in colloidal systems are very sluggish and colloidal suspensions are optically transparent. Therefore, colloidal systems are often discussed as model systems for metals. In the present work, we study the process of crystallization of charged colloidal systems from the very beginning. Charged colloids offer the advantage that the interaction potential can be systematically tuned by a variation of the particle number density and the salt concentration. We use light scattering and ultra-small angle x-ray scattering to investigate the formation of short-range order in the liquid state even far from equilibrium, crystal nucleation and crystal growth. The results are compared with those of equivalent studies on metallic systems. They are critically assessed as regards similarities and differences.
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Affiliation(s)
- Dieter M Herlach
- Institut für Materialphysik im Weltraum, Deutsches Zentrum für Luft- und Raumfahrt (DLR), 51147 Köln, Germany
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