Nanoscience and Nanotechnology Commons^™

Transport Of Water And Ions Through Single-Walled Armchair Carbon Nanotubes: A Molecular Dynamics Study, Michelle Patricia Aranha

Doctoral Dissertations

The narrow hydrophobic interior of a carbon nanotube (CNT) poses a barrier to the transport of water and ions, and yet, unexpectedly, numerous experimental and simulation studies have confirmed fast water transport rates comparable to those seen in biological aquaporin channels. These outstanding features of high water permeability and high solute rejection of even dissolved ions that would typically require a lot of energy for separation in commercial processes makes carbon nanotubes an exciting candidate for desalination membranes. Extending ion exclusion beyond simple mechanical sieving by the inclusion of electrostatics via added functionality to the nanotube bears promise to not …

The Rheology And Roll-To-Roll Processing Of Shear-Thickening Particle Dispersions, Sunilkumar Khandavalli

Doctoral Dissertations

Particle dispersions are ubiquitous in our daily lives ranging from food and pharmaceutical products to inks. There has been great interest in the recent years in formulation of functional inks to fabricate myriad flexible electronic devices through high-throughput roll-to-roll technologies. The formulations often contain several functional additives or rheological modifiers that can affect the microstructure, rheology and processing. Understanding the rheology of formulations is important for tuning the formulation for optimal processing. This thesis presents investigations on the rheology of particle dispersions and their impact on roll-to-roll technologies. Shear-thickening behavior is common in particle dispersions, particularly, concentrated particulate inks. We …

Solution-Based Assembly Of Conjugated Polymers Into Nanofibers For Organic Electronics, Daniel E. Acevedo Cartagena

Doctoral Dissertations

Solution-based crystallization of conjugated polymers offers a scalable and attractive route to develop hierarchical structures for electronic devices. The introduction of well-defined nucleation sites into metastable solutions provides a way to regulate the crystallization behavior, and therefore the morphology of the material. A crystallization method for generating metastable solutions of poly(3-hexylthiophene) (P3HT) was established. These metastable solutions allow P3HT to selectively crystallize into nanofibers (NFs) on graphene-coated surfaces. It was found that the crystallization kinetics is faster with increasing P3HT molecular weight and concentration. Through in situ atomic force microscopy, it was confirmed that NFs grow vertically in a face-on …

Guiding The Self-Assembly Of Block Copolymers In 2d And 3d With Minimal Patterning, Jaewon Choi

Doctoral Dissertations

Directed self-assembly (DSA) of block copolymers (BCPs) based on topographic patterns is one of the most promising strategies for overcoming resolution limitations in the current lithographic process and fabricating the next generation data storage devices. While the DSA of BCPs with deep topographic patterning has been extensively studied both experimentally and theoretically over the past two decades, less attention has been paid to the development of the DSA process using minimal topographic patterning. This dissertation focuses on understanding the effect of minimal topographic patterning on guiding the self-assembly of BCPs in 2D and 3D. We demonstrate that minimal trench patterns …

Advanced Purification And Direct-Write 3d Nanoprinting Via Focused Electron Beam Induced Deposition, Brett Bloxton Lewis

Doctoral Dissertations

This dissertation addresses three difficulties with focused electron beam induced deposition preventing broader application; purity, spatial control, and mechanical characterization.

Focused electron beam induced deposition (FEBID) has many advantages as a nanoscale fabrication tool. It is compatible for implementation into current lithographic techniques and has the potential to direct-write in a single step nanostructures of a high degree of complexity. FEBID is a very versatile tool capable of fabricating structures of many different compositions ranging from insulating oxides to conducting metals.

Due to the complexity of the technique and the difficulty in directly measuring many important variables, FEBID has remained …