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  1. Artikel: Quantitative Analysis of Electron Beam Damage in Organic Thin Films

    Leijten, Zino J.W. A / Keizer Arthur D. A / de With Gijsbertus / Friedrich Heiner

    The Journal of Physical Chemistry C. 2017 May 18, v. 121, no. 19

    2017  

    Abstract: In transmission electron microscopy (TEM) the interaction of an electron beam with polymers such as P3HT:PCBM photovoltaic nanocomposites results in electron beam damage, which is the most important factor limiting acquisition of structural or chemical ... ...

    Abstract In transmission electron microscopy (TEM) the interaction of an electron beam with polymers such as P3HT:PCBM photovoltaic nanocomposites results in electron beam damage, which is the most important factor limiting acquisition of structural or chemical data at high spatial resolution. Beam effects can vary depending on parameters such as electron dose rate, temperature during imaging, and the presence of water and oxygen in the sample. Furthermore, beam damage will occur at different length scales. To assess beam damage at the angstrom scale, we followed the intensity of P3HT and PCBM diffraction rings as a function of accumulated electron dose by acquiring dose series and varying the electron dose rate, sample preparation, and the temperature during acquisition. From this, we calculated a critical dose for diffraction experiments. In imaging mode, thin film deformation was assessed using the normalized cross-correlation coefficient, while mass loss was determined via changes in average intensity and standard deviation, also varying electron dose rate, sample preparation, and temperature during acquisition. The understanding of beam damage and the determination of critical electron doses provides a framework for future experiments to maximize the information content during the acquisition of images and diffraction patterns with (cryogenic) transmission electron microscopy.
    Schlagwörter deformation ; image analysis ; nanocomposites ; oxygen ; physical chemistry ; polymers ; quantitative analysis ; statistical analysis ; temperature ; transmission electron microscopy
    Sprache Englisch
    Erscheinungsverlauf 2017-0518
    Umfang p. 10552-10561.
    Erscheinungsort American Chemical Society
    Dokumenttyp Artikel
    ISSN 1932-7455
    DOI 10.1021%2Facs.jpcc.7b01749
    Datenquelle NAL Katalog (AGRICOLA)

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  2. Artikel: Quantitative Analysis of Electron Beam Damage in Organic Thin Films.

    Leijten, Zino J W A / Keizer, Arthur D A / de With, Gijsbertus / Friedrich, Heiner

    The journal of physical chemistry. C, Nanomaterials and interfaces

    2017  Band 121, Heft 19, Seite(n) 10552–10561

    Abstract: In transmission electron microscopy (TEM) the interaction of an electron beam with polymers such as P3HT:PCBM photovoltaic nanocomposites results in electron beam damage, which is the most important factor limiting acquisition of structural or chemical ... ...

    Abstract In transmission electron microscopy (TEM) the interaction of an electron beam with polymers such as P3HT:PCBM photovoltaic nanocomposites results in electron beam damage, which is the most important factor limiting acquisition of structural or chemical data at high spatial resolution. Beam effects can vary depending on parameters such as electron dose rate, temperature during imaging, and the presence of water and oxygen in the sample. Furthermore, beam damage will occur at different length scales. To assess beam damage at the angstrom scale, we followed the intensity of P3HT and PCBM diffraction rings as a function of accumulated electron dose by acquiring dose series and varying the electron dose rate, sample preparation, and the temperature during acquisition. From this, we calculated a critical dose for diffraction experiments. In imaging mode, thin film deformation was assessed using the normalized cross-correlation coefficient, while mass loss was determined via changes in average intensity and standard deviation, also varying electron dose rate, sample preparation, and temperature during acquisition. The understanding of beam damage and the determination of critical electron doses provides a framework for future experiments to maximize the information content during the acquisition of images and diffraction patterns with (cryogenic) transmission electron microscopy.
    Sprache Englisch
    Erscheinungsdatum 2017-05-09
    Erscheinungsland United States
    Dokumenttyp Journal Article
    ISSN 1932-7447
    ISSN 1932-7447
    DOI 10.1021/acs.jpcc.7b01749
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  3. Artikel ; Online: Spontaneous organization of supracolloids into three-dimensional structured materials.

    Moradi, Mohammad-Amin / Eren, E Deniz / Chiappini, Massimiliano / Rzadkiewicz, Sebastian / Goudzwaard, Maurits / van Rijt, Mark M J / Keizer, Arthur D A / Routh, Alexander F / Dijkstra, Marjolein / de With, Gijsbertus / Sommerdijk, Nico / Friedrich, Heiner / Patterson, Joseph P

    Nature materials

    2021  Band 20, Heft 4, Seite(n) 541–547

    Abstract: Periodic nano- or microscale structures are used to control light, energy and mass transportation. Colloidal organization is the most versatile method used to control nano- and microscale order, and employs either the enthalpy-driven self-assembly of ... ...

    Abstract Periodic nano- or microscale structures are used to control light, energy and mass transportation. Colloidal organization is the most versatile method used to control nano- and microscale order, and employs either the enthalpy-driven self-assembly of particles at a low concentration or the entropy-driven packing of particles at a high concentration. Nonetheless, it cannot yet provide the spontaneous three-dimensional organization of multicomponent particles at a high concentration. Here we combined these two concepts into a single strategy to achieve hierarchical multicomponent materials. We tuned the electrostatic attraction between polymer and silica nanoparticles to create dynamic supracolloids whose components, on drying, reorganize by entropy into three-dimensional structured materials. Cryogenic electron tomography reveals the kinetic pathways, whereas Monte Carlo simulations combined with a kinetic model provide design rules to form the supracolloids and control the kinetic pathways. This approach may be useful to fabricate hierarchical hybrid materials for distinct technological applications.
    Sprache Englisch
    Erscheinungsdatum 2021-01-28
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2088679-2
    ISSN 1476-4660 ; 1476-1122
    ISSN (online) 1476-4660
    ISSN 1476-1122
    DOI 10.1038/s41563-020-00900-5
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  4. Artikel ; Online: Mapping and Controlling Liquid Layer Thickness in Liquid-Phase (Scanning) Transmission Electron Microscopy.

    Wu, Hanglong / Su, Hao / Joosten, Rick R M / Keizer, Arthur D A / van Hazendonk, Laura S / Wirix, Maarten J M / Patterson, Joseph P / Laven, Jozua / de With, Gijsbertus / Friedrich, Heiner

    Small methods

    2021  Band 5, Heft 6, Seite(n) e2001287

    Abstract: Liquid-Phase (Scanning) Transmission Electron Microscopy (LP-(S)TEM) has become an essential technique to monitor nanoscale materials processes in liquids in real-time. Due to the pressure difference between the liquid and the microscope vacuum, bending ... ...

    Abstract Liquid-Phase (Scanning) Transmission Electron Microscopy (LP-(S)TEM) has become an essential technique to monitor nanoscale materials processes in liquids in real-time. Due to the pressure difference between the liquid and the microscope vacuum, bending of the silicon nitride (SiN
    Sprache Englisch
    Erscheinungsdatum 2021-05-05
    Erscheinungsland Germany
    Dokumenttyp Journal Article
    ISSN 2366-9608
    ISSN (online) 2366-9608
    DOI 10.1002/smtd.202001287
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

    Volltext online

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  5. Artikel ; Online: Liquid-liquid phase separation during amphiphilic self-assembly.

    Ianiro, Alessandro / Wu, Hanglong / van Rijt, Mark M J / Vena, M Paula / Keizer, Arthur D A / Esteves, A Catarina C / Tuinier, Remco / Friedrich, Heiner / Sommerdijk, Nico A J M / Patterson, Joseph P

    Nature chemistry

    2019  Band 11, Heft 4, Seite(n) 320–328

    Abstract: The self-assembly of amphiphilic molecules in solution is a ubiquitous process in both natural and synthetic systems. The ability to effectively control the structure and properties of these systems is essential for tuning the quality of their ... ...

    Abstract The self-assembly of amphiphilic molecules in solution is a ubiquitous process in both natural and synthetic systems. The ability to effectively control the structure and properties of these systems is essential for tuning the quality of their functionality, yet the underlying mechanisms governing the transition from molecules to assemblies have not been fully resolved. Here we describe how amphiphilic self-assembly can be preceded by liquid-liquid phase separation. The assembly of a model block co-polymer system into vesicular structures was probed through a combination of liquid-phase electron microscopy, self-consistent field computations and Gibbs free energy calculations. This analysis shows the formation of polymer-rich liquid droplets that act as a precursor in the bottom-up formation of spherical micelles, which then evolve into vesicles. The liquid-liquid phase separation plays a role in determining the resulting vesicles' structural properties, such as their size and membrane thickness, and the onset of kinetic traps during self-assembly.
    Sprache Englisch
    Erscheinungsdatum 2019-02-18
    Erscheinungsland England
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 2464596-5
    ISSN 1755-4349 ; 1755-4330
    ISSN (online) 1755-4349
    ISSN 1755-4330
    DOI 10.1038/s41557-019-0210-4
    Datenquelle MEDical Literature Analysis and Retrieval System OnLINE

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  6. Artikel ; Online: Supramolecular Double Helices from Small C

    Lafleur, René P M / Herziger, Svenja / Schoenmakers, Sandra M C / Keizer, Arthur D A / Jahzerah, Jahaziel / Thota, Bala N S / Su, Lu / Bomans, Paul H H / Sommerdijk, Nico A J M / Palmans, Anja R A / Haag, Rainer / Friedrich, Heiner / Böttcher, Christoph / Meijer, E W

    Journal of the American Chemical Society

    2020  Band 142, Heft 41, Seite(n) 17644–17652

    Abstract: Supramolecular fibers in water, micrometers long and several nanometers in width, are among the most studied nanostructures for biomedical applications. These supramolecular polymers are formed through a spontaneous self-assembly process of small ... ...

    Abstract Supramolecular fibers in water, micrometers long and several nanometers in width, are among the most studied nanostructures for biomedical applications. These supramolecular polymers are formed through a spontaneous self-assembly process of small amphiphilic molecules by specific secondary interactions. Although many compounds do not possess a stereocenter, recent studies suggest the (co)existence of helical structures, albeit in racemic form. Here, we disclose a series of supramolecular (co)polymers based on water-soluble benzene-1,3,5-tricarboxamides (BTAs) that form double helices, fibers that were long thought to be chains of single molecules stacked in one dimension (1D). Detailed cryogenic transmission electron microscopy (cryo-TEM) studies and subsequent three-dimensional-volume reconstructions unveiled helical repeats, ranging from 15 to 30 nm. Most remarkable, the pitch can be tuned through the composition of the copolymers, where two different monomers with the same core but different peripheries are mixed in various ratios. Like in lipid bilayers, the hydrophobic shielding in the aggregates of these disc-shaped molecules is proposed to be best obtained by dimer formation, promoting supramolecular double helices. It is anticipated that many of the supramolecular polymers in water will have a thermodynamic stable structure, such as a double helix, although small structural changes can yield single stacks as well. Hence, it is essential to perform detailed analyses prior to sketching a molecular picture of these 1D fibers.
    Sprache Englisch
    Erscheinungsdatum 2020-09-29
    Erscheinungsland United States
    Dokumenttyp Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.0c08179
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  7. Artikel: Supramolecular Double Helices from Small C₃-Symmetrical Molecules Aggregated in Water

    Lafleur, René P. M / Herziger, Svenja / Schoenmakers, Sandra M. C / Keizer, Arthur D. A / Jahzerah, Jahaziel / Thota, Bala N. S / Su, Lu / Bomans, Paul H. H / Sommerdijk, Nico A. J. M / Palmans, Anja R. A / Haag, Rainer / Friedrich, Heiner / Böttcher, Christoph / Meijer, E. W

    Journal of the American Chemical Society. 2020 Sept. 16, v. 142, no. 41

    2020  

    Abstract: Supramolecular fibers in water, micrometers long and several nanometers in width, are among the most studied nanostructures for biomedical applications. These supramolecular polymers are formed through a spontaneous self-assembly process of small ... ...

    Abstract Supramolecular fibers in water, micrometers long and several nanometers in width, are among the most studied nanostructures for biomedical applications. These supramolecular polymers are formed through a spontaneous self-assembly process of small amphiphilic molecules by specific secondary interactions. Although many compounds do not possess a stereocenter, recent studies suggest the (co)existence of helical structures, albeit in racemic form. Here, we disclose a series of supramolecular (co)polymers based on water-soluble benzene-1,3,5-tricarboxamides (BTAs) that form double helices, fibers that were long thought to be chains of single molecules stacked in one dimension (1D). Detailed cryogenic transmission electron microscopy (cryo-TEM) studies and subsequent three-dimensional-volume reconstructions unveiled helical repeats, ranging from 15 to 30 nm. Most remarkable, the pitch can be tuned through the composition of the copolymers, where two different monomers with the same core but different peripheries are mixed in various ratios. Like in lipid bilayers, the hydrophobic shielding in the aggregates of these disc-shaped molecules is proposed to be best obtained by dimer formation, promoting supramolecular double helices. It is anticipated that many of the supramolecular polymers in water will have a thermodynamic stable structure, such as a double helix, although small structural changes can yield single stacks as well. Hence, it is essential to perform detailed analyses prior to sketching a molecular picture of these 1D fibers.
    Schlagwörter composite polymers ; hydrophobicity ; lipid bilayers ; thermodynamics ; transmission electron microscopy ; water solubility
    Sprache Englisch
    Erscheinungsverlauf 2020-0916
    Umfang p. 17644-17652.
    Erscheinungsort American Chemical Society
    Dokumenttyp Artikel
    Anmerkung NAL-AP-2-clean
    ZDB-ID 3155-0
    ISSN 1520-5126 ; 0002-7863
    ISSN (online) 1520-5126
    ISSN 0002-7863
    DOI 10.1021/jacs.0c08179
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