Integration of Aligned Nanorod Array Structures into Fiber Raman Probes

智力优势：基于光纤的表面增强拉曼散射（Sers）探针具有抗电磁干扰、体积小、灵敏度高、选择性好、复用能力强、可远程检测、可嵌入纺织品结构中以及可在难以接近的位置检测分子的亚单层覆盖等优点。Sers光纤探针的一个关键方面是要求特定的表面形态以实现可再现和高水平的增强。目前的大多数制造技术难以生产可靠的、可重复的、坚固的、容易制造的和相对便宜的Sers探针。最近的PI已经证明，基于掠射角沉积（GLAD）的纳米纤维技术产生具有极高Sers增强因子的Ag纳米棒基底。此外，与现有的纳米纤维方法相比，GLAD方法提供了几个战略优势，包括：（1）精确控制纳米棒阵列的尺寸，形状，密度，排列，取向和组成，以及（2）使用相对简单的程序实现该方法。本项目的总体目标有两个方面：（1）从根本上了解金属纳米棒阵列的纳米结构设计（2）开发优化的Sers基底，包括平面基底和光纤基底，并将这些基底集成到基于光纤的Sers探针中。更广泛的影响：成功开发一种实用、简单和廉价的技术，用于制造新型纳米结构和集成光纤拉曼探针，将在以下领域产生巨大和直接的影响：i）纳米结构制造和工程，ii）基础表面科学，iii）分析光谱学，iv）化学传感，和v）生物分析应用。PI还将开发一个基于实验室的纳米技术课程模块，以帮助本科生和高中生获得纳米纤维的实践经验。

Intellectual Merits: Fiber optic-based Surface-Enhanced Raman scattering (SERS) probe has many advantages, including immunity to electromagnetic interference, small and compact size, sensitivity, selectivity, multiplexing ability, remote sensing, the ability to be embedded into textile structure and detection of sub-monolayer coverage of molecules at inaccessible locations. A critical aspect of SERS fiber probe is the requirement of a specific surface morphology to achieve reproducible and high levels of enhancement. Most of the current fabrication techniques have difficulty in producing dependable, reproducible, rugged, easily fabricated and relatively inexpensive SERS probe. Recent the PIs have demonstrated that a nanofabrication technique based on glancing angle deposition (GLAD) produces Ag nanorod substrates that exhibit extremely high SERS enhancement factors. Also, in comparison with existing nanofabrication methods, the GLAD method offers several strategic advantages, including: (1) precise control of the size, shape, density, alignment, orientation and composition of the nanorod arrays, and (2) implementation of the method using relatively simple procedures. The overall objective of this project is two-fold: (1) to fundamentally understand how the nanostructural design of metallic nanorod arrays (i.e. their size, shape, orientation, lateral arrangement and composition) influences SERS enhancement; and (2) to develop optimized SERS substrates, including both planar and fiber substrates, and to integrate these substrates into fiber optic-based SERS probes.Broader Impacts: The successful development of a practical, simple and inexpensive technique for fabrication of novel nanostructures and integrated fiber Raman probes would have a large and immediate impact in the areas of: i) nanostructure fabrication and engineering, ii) fundamental surface science, iii) analytical spectroscopy, iv) chemical sensing, and v) bioanalytical applications. The PIs will also develop a lab-based nanotechnology course module to help undergraduate and high school students to obtain hands-on experience on nanofabrication.