Realizing Hierarchically Ordered Porous Functional Materials from the Crystallization of Both Large-scale and Colloidal Particles

通过大尺寸和胶体颗粒的结晶实现分级有序的多孔功能材料

• 批准号: 1634917
• 负责人: Joseph McCarthy
• 金额: $ 40.42万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-07-15 至 2020-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1634917&HistoricalAwards=false
• 关键词: Realizing; Hierarchically; Ordered; Porous; Functional

Ordered porous materials hold promise for enhanced performance in a variety of fields. Often this class of materials are fabricated through a process called self-assembly, whereby the component parts of a macroscopic material spontaneously arrange themselves into a desired structure. While self-assembly of materials that are ordered at the nano-scale has recently captured the interest and imagination of scientists and engineers, the self-assembly of larger, meso- and macro- scale components can also have a dramatic impact on tissue engineering, microelectronics, energy, and 3-D visual displays. Nevertheless, despite these technical drivers, self-assembly at these larger scales has received little focus from the scientific and engineering communities and this area remains in its infancy. This award supports the study and development of methods of self-assembly that are amenable to the fabrication of ordered porous materials constructed of building blocks that are considerably larger than nano-materials (that is, in the tens to hundreds or micrometer size range). In addition to opening the approach of self-assembly to a whole new range of building blocks, a successful project in this area will also allow a combination of the new techniques with existing nano-scale methods to ultimately lead to the fabrication of materials that are ordered over an unprecedented range of size scales. It is expected that this new class of materials can lead to advances in applications ranging from tissue engineering (scaffolds) to fuel cell/battery electrode fabrication to pharmaceuticals, thus, results from this research will benefit the U.S. economy and society as a whole. This research involves combining expertise in chemistry, physics, engineering, and materials science. The multi-disciplinary approach will help broaden participation of underrepresented groups in research and positively impact engineering education.Colloidal crystallization is a staple of nano-scale particle self-assembly, however, until recently is has been a technique that was essentially unused at scales beyond several microns. This is due, in part, to the fact that the underlying thermal effects (i.e., Brownian motion) at these larger meso- and macro- scales are small enough that components become kinetically arrested in non-equilibrium states. The research team plans to use a combination of experimentation and modeling (coupled Discrete Element and Lattice Boltzmann methods) in order to further develop a promising series of new materials processing strategies that exploit recently uncovered instabilities of dilute fluid-particle systems at large (10s to 100s of microns) scales. Theoretical and scaling arguments will be used to determine the criteria necessary to induce the required instabilities. These new strategies will open particle crystallization techniques to a range of particle sizes that are typically well beyond the colloidal limit. Then, a combination of existing (colloidal) techniques with the new approaches can be used to fabricate novel hierarchically-ordered structures that mimic those found in nature (both in pore distribution as well as stoichiometry) and can ultimately form the basis of novel materials processing methods.

有序的多孔材料有望在各个领域提高性能。通常，这类材料是通过称为自组装的过程来制造的，从而使宏观材料的组成部分自发地将自己安排成所需的结构。尽管在纳米级订购的材料的自组装最近捕捉了科学家和工程师的兴趣和想象力，但较大，中级和宏观成分的自组装也可以对组织工程，微电子，能源，能源和3-D Visual显示器产生巨大影响。尽管如此，尽管这些技术驱动力，但在这些较大范围内的自组装几乎没有从科学和工程社区的重点，而且该领域仍处于起步阶段。该奖项支持自组装方法的研究和开发，这些方法适合于制造有序的多孔材料，这些材料由构建的构造块构成，这些材料比纳米材料大得多（即，在数十个或数百或微米的尺寸范围内）。除了将自组装的方法开放到一个全新的构建基础上，该领域的成功项目还将允许将新技术与现有的纳米尺度方法结合在一起，最终导致在尺寸尺寸尺寸范围范围内订购的材料的制造。可以预期，这种新的材料可以导致从组织工程（支架）到燃料电池/电池电极制造到药品的应用，因此，这项研究的结果将使美国的经济和整个社会受益。这项研究涉及将化学，物理，工程和材料科学方面的专业知识结合在一起。多学科的方法将有助于扩大代表性不足的群体在研究中的参与，并对工程教育产生积极影响。胶体结晶是纳米级粒子自我组装的主食，但是，直到最近，最近还是一种技术，在几微米以外的尺度上根本没有使用。这部分是由于以下事实：在这些较大的中间和宏观上，潜在的热效应（即布朗运动）足够小，以至于成分在非平衡状态下具有动力学捕获。研究小组计划结合实验和建模（耦合离散元素和晶格Boltzmann方法），以进一步制定一系列有希望的新材料加工策略，这些策略利用了最近发现的稀释流体 - 晶状体系统在大的（10s至100s微米）的尺度上。理论和缩放论点将用于确定诱导所需不稳定性所需的标准。这些新策略将向通常超出胶体极限的一系列粒径开放颗粒结晶技术。然后，现有的（胶体）技术与新方法的结合可以用于制造新型的层次结构结构，这些结构模仿自然界中发现的结构（包括孔分布和化学计量计），并最终构成新型材料处理方法的基础。