Now showing 1 - 3 of 3
  • Publication
    A review on 3D architected pyrolytic carbon produced by additive micro/nanomanufacturing
    ( 2024)
    Eggeler, Yolita M.
    ;
    Chan, Ka Chun
    ;
    un, Qing
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    Díaz Lantada, Andrés
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    Mager, Dario
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    Schwaiger, Ruth
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    Schröder, Rasmus
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    Wenzel, Wolfgang
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    Korvink, Jan G.
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    Monsur, Islam
    Additive micro/nano-manufacturing of polymeric precursors combining with a subsequent pyrolysis step enables the design-controlled fabrication of micro/nano-architected 3D pyrolytic carbon structures with complex architectural details. Pyrolysis results in a significant geometrical shrinkage of the pyrolytic carbon structure, leading to a structural dimension significantly smaller than the resolution limit of the involved additive manufacturing technology. Combining with the material properties of carbon and 3D architectures, architected 3D pyrolytic carbon exhibits exceptional properties, which are significantly superior to that of bulk carbon materials. This article presents a comprehensive review of the manufacturing processes of micro/nano-architected pyrolytic carbon materials, their properties, and corresponding demonstrated applications. Acknowledging the "young" age of the field of micro/nano-architected carbon, this article also addresses the current challenges and paints the future research directions of this field.
  • Publication
    In Situ Pyrolysis of 3D Printed Building Blocks for Functional Nanoscale Metamaterials
    ( 2024)
    Quing, Sun
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    Dolle, Christian
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    Kurpiers, Chantal
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    Kraft, Christian
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    Monsur, Islam
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    Schwaiger, Ruth
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    ;
    Eggeler, Yolita M.
    This study presents a novel approach for investigating the shrinkage dynamics of 3D-printed nanoarchitectures during isothermal pyrolysis, utilizing in situ electron microscopy. For the first time, the temporal evolution of 3D structures is tracked continuously until a quasi-stationary state is reached. By subjecting the 3D objects to different temperatures and atmospheric conditions, significant changes in the resulting kinetic parameters and morphological textures of the 3D objects are observed, particularly those possessing varying surface-to-volume ratios. Its results reveal that the effective activation energy required for pyrolysis-induced morphological shrinkage is approximately four times larger under vacuum conditions than in a nitrogen atmosphere (2.6 eV vs. 0.5-0.9 eV, respectively). Additionally, a subtle enrichment of oxygen on the surfaces of the structures for pyrolysis in nitrogen is found through a postmortem electron energy loss spectroscopy study, differentiating the vacuum pyrolysis. These findings are examined in the context of the underlying process parameters, and a mechanistic model is proposed. As a result, understanding and controlling pyrolysis in 3D structures of different geometrical dimensions not only enables precise modification of shrinkage and the creation of tensegrity structures, but also promotes pyrolytic carbon development with custom architectures and properties, especially in the field of carbon micro- and nano-electromechanical systems.
  • Publication
    In situ pyrolysis of 3D printed microstructures - an ESEM study
    ( 2022)
    Sun, Qing
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    Dolle, Christian
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    Kurpiers, Chantal
    ;
    Schwaiger, Ruth
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    ;
    Eggeler, Yolita M.