Nonequilibrium Materials Synthesis: Understanding and Controlling the Formation of Hierarchically Structured Microtubes

技术总结这个项目的重点是在空间控制的反应过程中形成的无机管状材料。这些中空管的内径为1-100微米，是无定形二氧化硅和金属氢氧化物沉淀的结果。这一总体现象还没有得到很好的理解，其作为系统级材料科学示范案例的潜力也没有得到广泛的探索。根据这笔赠款，在材料研究部固态和材料化学计划的支持下，PI将开发一种压力控制反应堆系统，以生产半径最小为1微米的毫米长微管。此外，这些微管的大小和形状将通过可变电场和压力变化来控制。另一个中心目标是通过结合、捕获和吸附各种分子和粒子来对管壁的物理化学特征进行纳米工程。此外，该小组将把管子集成到微流控设备中，在那里它们将增加增强分离区域、化学传感器和催化处理站等功能。这些实验项目将得到模拟工作的补充，这些模拟工作旨在开发一个反应-传输模型，该模型能够根据降水动力学、扩散和平流过程捕捉大规模增长动力学的关键方面。该项目更广泛影响的一个重要部分是向非专家传达其主要想法和结果。该项目将通过一个多方面的视频外展计划来实现这一目标。此外，它还将促进佛罗里达州立大学本科生、研究生和博士后的教育。非技术性总结现代技术生产材料和设备的方式与生物系统使用的策略根本不同。这些差异可能解释了为什么具有分层结构和自我修复功能的材料往往会避开传统的工程方法，但在生物学中却大量存在。在这方面的一个关键问题是，化学反应如何导致形成比单个分子大几千到几百万倍的复杂结构。该项目将通过研究已知会产生中空管的无机反应来解决这个大问题。这些刚性结构的直径和长度与人类头发相当，但也可以明显更薄。管壁通常由无定形二氧化硅(多孔玻璃)和金属氢氧化物或氧化物组成，这产生了有趣的催化和光学性能。如果成功，这项研究将(I)建立纳米到宏观生长过程的量化模型，(Ii)提供可以在生长过程中塑造管子的反应堆系统，(Iii)展示引入化学传感和/或处理能力的壁材的化学修饰，(Iv)探索微流控和芯片实验室技术的应用。该项目还旨在将其科学思想和结果传达给非专家。这一基本现象引人入胜的栩栩如生的外观和整体视觉吸引力将极大地有助于这一努力。具体计划包括通过FSU的全球教育外展计划、播客和YouTube等流行网站进行有针对性的视频外展。此外，该项目还将促进几名本科生、研究生和博士后的教育。PI还将继续致力于让代表不足的群体参与，并参与旨在提高他们在研究和学术界中的领导作用的项目。

TECHNICAL SUMMARYThis project focuses on inorganic, tubular materials formed during spatially controlled reaction processes. These hollow tubes have inner radii 1-100 µm and result from the precipitation of amorphous silica and metal hydroxides. The overall phenomenon is not well understood and its potential as a model case for system-level materials science widely unexplored. Under this grant, supported by the Solid State and Materials Chemistry program of the Division of Materials Research, the PI will develop a pressure-controlled reactor system to produce millimeter-long microtubes with radii of down to 1 µm. In addition, the size and shape of these microtubes will be controlled using variable electric fields and pressure changes. Another central goal is to nano-engineer the physico-chemical characteristics of the tube wall by binding, trapping and adsorbing a variety of molecules and particles. Moreover, the group will integrate tubes into microfluidic devices where they will add functionalities such as enhanced separation regions, chemical sensors, and catalytic processing stations. These experimental projects will be complemented by modeling efforts that aim to develop a reaction-transport model capable of capturing key aspects of the large-scale growth dynamics based on the precipitation kinetics, diffusion, and advection processes. An important part of the broader impact of this project is to communicate its key ideas and results to non-experts. The project will pursue this goal through a multi-faceted video outreach program. In addition, it will advance the education of undergraduate, graduate and postdoctoral students at the Florida State University.NON-TECHNICAL SUMMARYModern technologies produce materials and devices in ways that differ fundamentally from the strategies employed by biological systems. These differences are the likely explanation as to why materials with hierarchical architectures and self-healing features tend to elute conventional engineering approaches but are abundant in biology. A key question in this context is how chemical reactions can cause the formation of complex structures that are thousands to millions times larger than the individual molecules. The project will tackle this big question by studying inorganic reactions that are known to produce hollow tubes. The diameter and length of these rigid structures is comparable to human hair but can also be significantly thinner. The tube walls typically consist of amorphous silica (porous glass) and metal hydroxides or oxides, which create interesting catalytic and optical properties. If successful, this research will (i) result in quantitative models of nano-to-macro growth processes, (ii) provide reactor systems that can shape the tubes during growth, (iii) demonstrate chemical modifications of the wall material that introduce chemical sensing and/or processing capabilities, (iv) explore applications towards uses in microfluidic and lab-on-a-chip technologies. The project also aims to communicate its scientific ideas and results to non-experts. The intriguing life-like appearance and overall visual appeal of the basic phenomenon will greatly assist in this effort. Specific plans include targeted video outreach through FSU's Global Educational Outreach Program, Podcasts, and popular websites such as YouTube. In addition, the project will advance the education of several undergraduate, graduate and postdoctoral students. The PI will also continue his commitment to involve underrepresented groups and participate in programs that aim to increase their leadership roles in research and academia.