Dielectrophoresis Directed Scalable Nanocolloidal Assembly

本项目的研究目标是探索指导胶体组装的新方法，以实现各种结构化功能纳米材料的稳健、可控和可扩展的制造。具体地说，将探索在不同频率和电压的交变电场下利用介电泳法(DEP)组装纳米胶体构建块，以制备分级纳米结构材料和器件，旨在开发典型的纳米级制造方案。由于目前对纳米胶体DEP行为的认识还不够深入，本文将以10-100 nm的胶乳纳米粒子为模型体系，考察和理解纳米尺度的交流极化和DEP诱导动力学的基本原理。为了实现原位和灵敏的实验表征，超快单粒子荧光光谱技术与微流控装置相结合，将被用来检测纳米胶体DEP特征与胶体尺寸、电导和介质电导率的尺度关系，从而可以有效地尺度不同胶体尺寸和悬浮条件的分级纳米胶体组装的纳米制造。如果成功，各种纳米胶体构件在交流电场下的定向组装可以发展成为一种实用和通用的方法，实现健壮、可控和可扩展的纳米制造和结构化功能纳米材料、复合材料和涂层的纳米制造。当与当前的微流体技术相结合时，基于DEP的纳米胶体操纵和组装方法将具有变革性并广泛应用于新兴的生物/纳米技术，如新型光子材料和多孔分离膜的合成、生物传感器和蛋白质晶体阵列的快速制造。研究生和本科生参与者，以及包括工程专业女学生在内的代表性不足的少数群体，将通过课堂教学和实验室研究，接受新的和先进的纳米材料合成和表征技术培训。该项目还寻求与相关工业企业建立强大的联盟，帮助学生、科学家和工程师更好地合作。

The research objective of this project is to investigate new methods to direct colloidal assembly for robust, controllable and scalable manufacturing of various structured functional nanomaterials. Specifically, dielectrophoresis (DEP)-directed assembly of nanocolloidal building blocks under ac-electric fields of varied frequency and voltage will be explored to produce hierarchical nanostructured materials and devices, aiming to a development of prototypical nanoscale manufacturing schemes. Owing to the currently inadequate understanding of nanocolloidal DEP behaviors, the fundamental of nanoscale ac-polarization and DEP-induced dynamics will be examined and understood with latex nanoparticles of varied size from 10-100 nm in aqueous media as a model system. To enable in-situ and sensitive experimental characterization, ultrafast singe-particle fluorescence spectroscopy technique integrated with microfluidic devices will be employed to examine the scaling of nanocolloidal DEP characteristics with colloidal size and conductance and medium conductivity, which can be used to effectively scale the nanomanufacturing of hierarchical nanocolloidal assembly with varied colloidal dimension and suspension condition. If successful, directed assembly of various nanocolloidal building blocks under ac-electric fields can be developed as a practical and versatile method to achieve robust, controllable and scalable nanofabrication and nanomanufacturing of structured functional nanomaterials, composites and coatings. When combined with current microfluidics technology, the DEP-based approach for nanocolloidal manipulation and assembly can be transformative and broadly applied to emerging bio/nanotechnology, such as the synthesis of novel photonic materials and porous separation membranes, rapid fabrication of biosensors and protein crystal arrays. Graduate and undergraduate student participants, as well as underrepresented minorities including female students in engineering majors, will be trained with new and advanced nanomaterials synthesis and characterization techniques through classroom instruction and laboratory research. This project also seeks to establish a strong coalition with relevant industrial corporations to help students, scientists and engineers work well together.