Deformation of hierarchical and anisotropic porous solids by fluid adsorption

流体吸附引起的分级和各向异性多孔固体的变形

• 批准号: 252047785
• 负责人: Dr. Gudrun Reichenauer
• 金额: --
• 依托单位: Bayerisches Zentrum für Angewandte Energieforschung e.V. (ZAE Bayern)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2014
• 资助国家: 德国
• 起止时间: 2013-12-31 至 2018-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/252047785?language=en
• 关键词: Deformation; hierarchical; anisotropic; porous; solids

The goal of the proposed research is to enhance the fundamental understanding of adsorption-induced deformation in monolithic materials with hierarchical porosity. Macroporous networks consisting of struts of ordered mesoporous silica with microporous walls will be synthesized, while controlling pore size, pore volume-fraction, and particularly also pore anisotropy at all hierarchy levels. Adsorption-induced deformation will be investigated quantitatively at the level of the mesopore system as well as on the macroscopic level. The central motivation for the proposed research is to derive basic correlations between the physico-chemical parameters of adsorption-induced deformation at the nanometer scale, and the hierarchical and anisotropic network structure with resulting actuated mechanical behavior at the macroscopic level. This knowledge forms the basis for future applications of hierarchically organized porous systems in designed switchable components. The basic goals and innovative aspects of the proposed research are the following:New synthesis approaches will be developed to tailor the degree of anisotropy in monolithic silica with hierarchical porosity at different levels, while controlling fluid-wall interaction and microporosity. Synthesis is based on sol-gel routes under external force fields such as shear or uniaxial compression. Model carbon and silicon replica will be derived from these silica monoliths by hard templating and reactive conversion, respectively.Different length scales and anisotropy will be explicitly considered experimentally in the investigation of adsorption-induced deformation. Structural investigations using synchrotron radiation based techniques will allow characterizing structure at all scales. A unique combination of in-situ techniques applied during fluid adsorption (in-situ X-ray diffraction and in-situ dilatometry) will be used to quantitatively derive the influence of hierarchy on the macroscopic response to the fluid induced deformation at the nanometer level. Designated Model fluids will be n-Pentane and N2 for derivation of fundamental relationships and H2O as a more complex adsorptive towards applications.Hierarchical mechanical models of adsorption-induced deformation will be developed and validated. They are based on analytical and/or numerical models for single mesopore deformation, coupled with finite element calculations to derive the macroscopic strains. The project combines unique and complementary expertise of three experimental groups in Austria and Germany, supported by an international cooperation partner working on the theory of adsorption- induced deformation. The expected outcomes of this basic research project are believed to fertilize both, theoreticians and modeling groups working on a better understanding of sorption-induced deformation in general, as well as applied scientists developing devices for sensing and actuation, for energy related application, and for catalysis.

提出的研究的目标是提高吸附诱导变形的整体材料的层次孔隙率的基本理解。将合成由具有微孔壁的有序中孔二氧化硅的支柱组成的大孔网络，同时控制孔径、孔体积分数，特别是在所有层次水平的孔各向异性。吸附诱导变形将在介孔系统的水平，以及在宏观水平上进行定量研究。所提出的研究的主要动机是在纳米尺度上获得吸附诱导变形的物理化学参数之间的基本相关性，以及在宏观水平上产生的致动力学行为的分层和各向异性网络结构。这种知识形成的基础上，未来的应用程序的分层组织的多孔系统设计的可切换组件。所提出的研究的基本目标和创新方面如下：新的合成方法将被开发，以定制在不同层次的分层孔隙度的整体二氧化硅的各向异性的程度，同时控制流体壁的相互作用和微孔。合成是基于在外力场如剪切或单轴压缩下的溶胶-凝胶路线。模型碳和硅的复制品将分别通过硬模板和反应转化从这些二氧化硅单块中获得。不同的长度尺度和各向异性将被明确地考虑在实验中的吸附诱导变形的研究。使用基于同步辐射的技术进行结构研究将允许表征所有尺度的结构。流体吸附过程中应用的原位技术（原位X射线衍射和原位衍射）的独特组合将被用来定量推导出在纳米级流体诱导变形的宏观响应的层次结构的影响。指定的模型流体将是正戊烷和N2，用于推导基本关系，H2O作为更复杂的吸附剂，用于应用。将开发和验证吸附诱导变形的分层力学模型。它们是基于单个中孔变形的分析和/或数值模型，再加上有限元计算，以获得宏观应变。 该项目结合了奥地利和德国三个实验小组独特和互补的专业知识，得到了一个致力于吸附诱导变形理论的国际合作伙伴的支持。这个基础研究项目的预期成果被认为将有助于理论家和建模小组更好地理解一般吸附诱导的变形，以及应用科学家开发用于传感和驱动，能源相关应用和催化的设备。