Physical Sciences and Mathematics Commons^™

Studies On Purification And Functionalization Of Carbon Nanotubes And Their Aqueous Phase Behavior, Zheqiong Wu

Dissertations

Carbon nanotubes (CNTs) are known to have unique mechanical, thermal and electrical properties which make them attractive for a wide range of applications ranging from batteries to sensors. CNTs are rolled up graphene sheets where the single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) are classified according to the number of concentric rings. In this dissertation, the focus is on several different aspects of MWCNTs. These include purification, functionalization and colloidal behavior.

MWCNTs are insoluble in solvents and therefore some degree of functionalization is required prior to their real-world applications. Oxidation debris is generated during carboxylation which is usually the first …

Incorporating Carbon Nanotubes Into Carbon Fiber Via Surface Modification, Robert Benjamin Ripy

Masters Theses

Ever more advanced materials need to be designed to further the exploration of avenues of science and engineering. Metals and traditional composites are not meeting the needs of today’s stringent demands for lightweight and strong materials. There is a need for advanced materials that are lighter and stronger to replace conventional materials; carbon fiber composites became the obvious choice because of their outstanding mechanical properties. Polyacrylonitrile (PAN) based carbon fiber has reached its apex in terms of its strength to weight ratio. Carbon nanotubes (CNTs) offer a lightweight and potentially stronger alternative to PAN based fibers. However, it is difficult …

Removal Of Perfluorooctanoic Acid From Water Using Primitive, Conventional And Novel Carbonaceous Sorbent Materials, Christopher K. Brown

Theses and Dissertations

Polyfluoroalkyl Substances (PFAS), like perfluorooctanoic acid, have been used for the last 50 years in a wide variety of industrial processes and consumer-based products, including polymer additives, lubricants, fire retardants and suppressants, pesticides, and surfactants (Buck et al. 2015). The Department of Defense (DoD) has used PFAS-based Aqueous Film Forming Foam (AFFF) at fire training facilities and aircraft hangars. AFFF has contaminated approximately 600 sites classified as fire training facilities with PFAS (Huang, 2013).

This study focused on testing the most likely carbonaceous adsorbent compounds to remediate PFAS-contaminated sites on Air Force installations. Batch tests were performed to determine the …

Toward High Performance Nanocarbon Fibers, Michaela R. Pfau

Master's Theses

High performance carbon fibers (CFs) have been a commercially available since their commercial boom in the 1970s, and are generally produced via carbonization of poly (acrylonitrile) (PAN). More recently, carbon nanomaterials like graphene and carbon nanotubes (CNTs) have been discovered and have shown excellent mechanical, thermal, and electrical properties due to their sp² carbon repeating structure. Graphene and CNTs can both be organized into macroscopic fibers using a number of different techniques, resulting in fibers with promising mechanical performance that can be readily multifunctionalized. In some cases, the two materials have been combined, and the resulting hybrid fibers have …

Degradation And Exciton Energy Transfer Studies In Single-Walled Carbon Nanotube Bundles, Abhishek Gottipati

Legacy Theses & Dissertations (2009 - 2024)

Single walled carbon nanotubes (SWNTs) due to their unique optical behavior, large surface area, robust mechanical strength and electrical properties make them one of the ideal candidates for sensing and opto-electronic applications. In this work, we explore the energy transfer (exciton energy transfer-EET) phenomena occurring between nanotubes in bundles, using resonance Raman spectroscopy.