DMREF: Mechanics of Three-Dimensional Carbon Nanotube Aerogels with Tunable Junctions

这个设计材料革命和工程师我们的未来（DMREF）赠款提供资金，用于系统和全面地了解三维碳纳米管气凝胶的机械性能如何取决于孔几何形状，孔径分布和纳米管之间的连接特性，以提高性能并预测基于纳米管的多孔结构的最佳设计。纳米管气凝胶的机械性能可以很容易地通过修改的交界处或？节点？在纳米管之间。例如，用石墨烯层涂覆节点将这些气凝胶转变成超弹性和抗疲劳材料。此外，纳米管气凝胶是几乎理想的刚性棒网络的一个强有力的例子，并且适合于与刚性棒的理想膨胀网络的模拟进行比较。该项目将开始与纳米管气凝胶，包括现实的网络结构，以及纳米管和连接特性，近似实验系统的三维力学模型的发展。然后将测量气凝胶的机械性能，包括模量和滞后，作为网络和结参数的函数。通过改变结特性，将调查可用的纳米管气凝胶特性的范围，以提供对期望的（和不利的）结特性的洞察和指导。模拟的指导将转化为制造具有不同连接点的三维纳米管网络，这些连接点涂覆有石墨烯，共价交联，并与连续杂化键融合。如果成功，这项研究的结果不仅有助于深入理解高度多孔网络的行为，而且具有重要的实际应用价值。具有高表面积和机械完整性的导电和多孔材料作为电池、燃料电池和超级电容器中的改进的电极材料被积极地寻求用于能量应用。通过计算结合实验来预测、设计和合成这些结构的能力将推进电极材料的设计步伐，并将作为推进其他多孔材料的模型。

This Designing Materials to Revolutionize and Engineer our Future (DMREF) grant provides funding for the development of a systematic and comprehensive understanding of how the mechanical properties of three-dimensional carbon nanotube aerogels depend on pore geometry, pore size distribution, and the characteristics of the junctions between nanotubes to improve the performance and to predict an optimal design of nanotube based porous structures. The mechanical properties of the nanotube aerogels can be readily manipulated via modification of the junctions or ?nodes? between the nanotubes. For example, coating the nodes with graphene layers transforms these aerogels into superelastic and fatigue resistant materials. Further, the nanotube aerogel is a strong example of a nearly ideal rigid rod network, and lends itself for comparison with simulations of an ideal percolating network of rigid rods. The project will begin with the development of three-dimensional mechanical models for nanotube aerogels that include realistic network structures as well as nanotube and junction properties that approximate experimental system. The mechanical properties of the aerogels, including modulus and hysteresis, as a function of network and junction parameters will then be measured. By varying the junction properties, the range of available nanotube aerogel properties will be surveyed in order to provide insight and guidance on desirable (and unfavorable) junction characteristics. The guidance from simulations will then be translated to fabricate three-dimensional nanotube networks with diverse junctions that are coated with graphene, covalently crosslinked, and fused with continuous hybridized bonds.If successful, the results of this research will not only facilitate the development of a deep understanding of the behavior of highly porous networks, but also have significant practical applications. Conducting and porous materials with high surface area and mechanical integrity are actively sought for energy applications as an improved electrode material in batteries, fuel cells, and supercapacitors. The ability to predict, design, and synthesize these structures with computation coupled with experiment will advance the pace at which electrode materials can be designed, and will serve as a model for advancing other porous materials.