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Publicly Accessible Penn Dissertations

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Full-Text Articles in Nanoscience and Nanotechnology

Microlamination Based Lumped And Distributed Magnetic Mems Systems Enabled By Through-Mold Sequential Multilayer Electrodeposition Technology, Yuan Li Jan 2018

Microlamination Based Lumped And Distributed Magnetic Mems Systems Enabled By Through-Mold Sequential Multilayer Electrodeposition Technology, Yuan Li

Publicly Accessible Penn Dissertations

Microfabricated magnetic MEMS components such as permanent micromagnets and soft magnetic structures are key enablers in various lumped and distributed systems such as energy harvesters, magnetometers, biomagnetic filters, and electromagnetic micromotors. The unique functionalities of such systems often require designers to controllably scale the relevant dimensions of a device relative to the characteristic length of a targeted application. We demonstrate in this dissertation that the developed Microlamination Technology could create two-dimensional uniform- or dual- height monolithic metallic structures with additional deterministic structural and compositional complexities along thickness direction, suitable to facilely and flexibly fabricate both lumped and distributed magnetic MEMS ...


Characterizing The Energetic Landscape In Solution Processable Solar Cells Via Frequency-Dependent Impedance Measurements, Eric S. Wong Jan 2018

Characterizing The Energetic Landscape In Solution Processable Solar Cells Via Frequency-Dependent Impedance Measurements, Eric S. Wong

Publicly Accessible Penn Dissertations

This thesis presents measurements and analyses aimed at describing charge transport dynamics in quantum dot (QD) photovoltaics (PVs). Due to their solution processability and unique size-dependent optoelectronic properties, ensembles of electronically coupled QDs (QD solids) provide an exciting platform for next generation PV devices. However, the structural disorder associated with the formation of conductive QD solids gives rise to a complicated density of states (DOS) emerging from the distribution of mesoscale charge dynamics occurring in these materials.

I present phenomological models to describe the DOS in the disordered energetic and spatial landscape of QD solids that relies on a suite ...


Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda Jan 2018

Two-Dimensional Nanopore And Nanoporous Devices For Molecular Sensing And Ion Selectivity, Gopinath Danda

Publicly Accessible Penn Dissertations

Nanopore-based devices provide the ability to detect, analyze and manipulate molecules by monitoring changes in ionic current and sieving molecules dissolved in an electrolyte. While devices with single nanopores can be used as molecular sensors and analyzers, including as a possible high-throughput DNA sequencer, devices with multiple nanopores (nanoporous devices) can be used to filter out ions from solutions, with possible use in water desalination. Sensitivity and molecular flux can be enhanced by using two-dimensional (2D) materials, like graphene and transition metal dichalcogenides (TMDs), as the nanopore membrane. However, these devices face challenges yet to be solved, including (a) fast ...


Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner Jan 2017

Flexible, Photopatterned, Colloidal Cdse Semiconductor Nanocrystal Integrated Circuits, Franklin Scott Stinner

Publicly Accessible Penn Dissertations

As semiconductor manufacturing pushes towards smaller and faster transistors, a parallel goal exists to create transistors which are not nearly as small. These transistors are not intended to match the performance of traditional crystalline semiconductors; they are designed to be significantly lower in cost and manufactured using methods that can make them physically flexible for applications where form is more important than speed. One of the developing technologies for this application is semiconductor nanocrystals.

We first explore methods to develop CdSe nanocrystal semiconducting “inks” into large-scale, high-speed integrated circuits. We demonstrate photopatterned transistors with mobilities of 10 cm2/Vs on ...


Nano/Biosensors Based On Large-Area Graphene, Pedro Jose Ducos Jan 2017

Nano/Biosensors Based On Large-Area Graphene, Pedro Jose Ducos

Publicly Accessible Penn Dissertations

Two dimensional materials have properties that make them ideal for applications in chemical and biomolecular sensing. Their high surface/volume ratio implies that all atoms are exposed to the environment, in contrast to three dimensional materials with most atoms shielded from interactions inside the bulk. Graphene additionally has an extremely high carrier mobility, even at ambient temperature and pressure, which makes it ideal as a transduction device. The work presented in this thesis describes large-scale fabrication of Graphene Field Effect Transistors (GFETs), their physical and chemical characterization, and their application as biomolecular sensors. Initially, work was focused on developing an ...


Filomicelles Deliver A Chemo-Differentiative Therapy To Durably Control Carcinoma Cell Fate, Praful Raveendran Nair Jan 2017

Filomicelles Deliver A Chemo-Differentiative Therapy To Durably Control Carcinoma Cell Fate, Praful Raveendran Nair

Publicly Accessible Penn Dissertations

Current chemotherapy causes a host of side effects and better delivery of drugs to tumors is required to reduce this. Nanocarriers have been proven to not only deliver better to tumors but also solubilize more drugs in the core, with flexible ‘filomicelles’ being particularly effective. They are still open to improvements and one obvious way is to increase drug loading and hence drug dosage delivered to tumors. In the first part, the core of filomicelles was modified by the integration of aromatic groups into the hydrophobic block of a degradable di-block copolymer with the aim of improving delivery of aromatic ...


Understanding Dewetting Transitions On Nanotextured Surfaces: Implications For Designing Surfaces With Improved Wettability, Suruchi Fialoke Jan 2017

Understanding Dewetting Transitions On Nanotextured Surfaces: Implications For Designing Surfaces With Improved Wettability, Suruchi Fialoke

Publicly Accessible Penn Dissertations

Despite the early promise of superhydrophobic surfaces, their widespread technological adoption has been dawdled by the ease with which water can penetrate the surface texture, resulting in a breakdown of superhydrophobicity. Furthermore, this breakdown is believed to be irreversible, because large adhesion barriers impede the dewetting of the surface texture and the concomitant recovery of superhydrophobicity. Using molecular dynamics simulations in conjunction with advanced sampling techniques, in this thesis, we challenge this conventional argument. We show that while large barriers do typically impede the recovery of superhydrophobicity, it can nevertheless be recovered spontaneously on nanotextured surfaces, wherein collective water density ...


Beyond Graphene: Monolayer Transition Metal Dichalcogenides, A New Platform For Science, Carl Hugo Naylor Jan 2017

Beyond Graphene: Monolayer Transition Metal Dichalcogenides, A New Platform For Science, Carl Hugo Naylor

Publicly Accessible Penn Dissertations

Following the isolation of graphene in 2004, scientists quickly showed that it possesses remarkable properties. However, as the scientific understanding of graphene matured, it became clear that it also has limitations: for example, graphene does not have a bandgap, making it poorly suited for use in digital logic. This motivated explorations of monolayer materials “beyond graphene”, which could embody functionalities that graphene lacks. Transition metal dichalcogenides (TMDs) are leading candidates in this field. TMDs possess a wide variety of properties accessible through the choice of chalcogen atom, metal atom and atomic configuration (1H, 1T, and 1T’). Similar to graphene, monolayer ...


Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour Jan 2017

Design And Synthesis Of Gold Nanoparticle Contrast Agents For Atherosclerosis Imaging With Computed Tomography, Peter Chhour

Publicly Accessible Penn Dissertations

Cell tracking offers the opportunity to study migration and localization of cells in vivo, allowing investigations of disease mechanisms and drug efficacy. Monocytes play a key role in the progression of atherosclerotic plaques in the coronary arteries. While x-ray computed tomography (CT) is commonly used to clinically assess coronary plaque burden, cell tracking with CT is mostly unexplored. The establishment of monocyte cell tracking tools would allow for the direct investigation of gene and drug therapies aimed at monocyte recruitment in atherosclerosis. In this thesis, we present the design and optimization of gold nanoparticles as CT contrast agents for cell ...


Synthesis Of Hybrid Nanomaterials Through Amphiphilic Self-Assembly, Qingjie Luo Jan 2016

Synthesis Of Hybrid Nanomaterials Through Amphiphilic Self-Assembly, Qingjie Luo

Publicly Accessible Penn Dissertations

There have been tremendous efforts toward combining nanoparticles, polymers, biomolecules in material synthesis and device fabrication in order to take advantage of the unique properties of each component. The ability to construct multicomponent hybrid nanomaterials with controllable structure and properties is critical to truly exploit the potential of these functional materials in many applications. This thesis presents the construction of self-assemblies of various components including nanoparticles, synthetic block copolymers, DNA block copolymers, and lipid molecules.

The location of nanoparticles in colloidal block copolymer assemblies is controlled by using nanoparticles modified with mixed surface ligands. Different morphologies including micelles, Janus-like micelles ...


Development And Characterization Of Next-Generation Contact Materials For Nanoelectromechanical Switches, Frank Streller Jan 2016

Development And Characterization Of Next-Generation Contact Materials For Nanoelectromechanical Switches, Frank Streller

Publicly Accessible Penn Dissertations

Nanoelectromechanical (NEM) switches were identified by the semiconductor industry as a low-power "beyond CMOS" technology. However, the reliability of the contact interface currently limits the commercialization of NEM switches, as the electrical contact has to be able to physically open and close up to a quadrillion (10^15) times without failing due to adhesion (by sticking shut) or contamination (reducing switch conductivity). These failure mechanisms are not well understood, and materials that exhibit the needed performance have not been demonstrated. Thus, commercially viable NEM switches demand the development of novel contact materials along with efficient methods to evaluate the performance ...


Nano-Bio Hybrid Electronic Sensors For Chemical Detection And Disease Diagnostics, Nicholas John Kybert Jan 2015

Nano-Bio Hybrid Electronic Sensors For Chemical Detection And Disease Diagnostics, Nicholas John Kybert

Publicly Accessible Penn Dissertations

The need to detect low concentrations of chemical or biological targets is ubiquitous in environmental monitoring and biomedical applications. The goal of this work was to address challenges in this arena by combining nanomaterials grown via scalable techniques with chemical receptors optimized for the detection problem at hand. Advances were made in the CVD growth of graphene, carbon nanotubes and molybdenum disulfide. Field effect transistors using these materials as the channel were fabricated using methods designed to avoid contamination of the nanomaterial surfaces. These devices were used to read out electronic signatures of binding events of molecular targets in both ...


Improving The Signal-To-Noise Of Nanopore Sensors, Matthew Puster Jan 2015

Improving The Signal-To-Noise Of Nanopore Sensors, Matthew Puster

Publicly Accessible Penn Dissertations

Over the last five years, solid state nanopore technology advanced to rival biological pores as a platform for next generation DNA sequencing. Fabrication improvements led to a reduction in nanopore diameter and membrane thickness, offering high precision sensing. Custom electronics were developed concomitant with low capacitance membranes for low-noise, high-bandwidth measurements. These advances improved our ability to detect small differences between translocating molecules and to measure short molecules translocating at high speeds.

This work focuses specifically on the challenge of maximizing the signal magnitude generated by the solid state nanopore. One way that this can be achieved is by thinning ...


Optical And Electronic Interactions At The Nanoscale, Michael Edward Turk Jan 2015

Optical And Electronic Interactions At The Nanoscale, Michael Edward Turk

Publicly Accessible Penn Dissertations

In this dissertation, we discuss optical and electronic interactions in three nanometer scale semiconductor systems in a broadly defined sense. These studies are performed using time-integrated and time-resolved optical spectroscopies and temperature- and field-dependent electrical transport measurements. We first discuss the construction and optimization of an optical apparatus for performing broadband, time-integrated and sub-picosecond fluorescence and absorption measurements. Using this apparatus, we then characterize the impact on the optically-excited carrier relaxation dynamics of cadmium selenide quantum dots due to a surface treatment previously shown to increase interparticle coupling, namely the solution exchange of native, aliphatic ligands for thiocyanate followed by ...


Engineering Novel Nanostructures Via Chemical And Morphological Transformations, Rahul Agarwal Jan 2015

Engineering Novel Nanostructures Via Chemical And Morphological Transformations, Rahul Agarwal

Publicly Accessible Penn Dissertations

Materials at the nanoscale have revolutionized the world around us by enabling the discovery of novel size dependent properties and experimental verification of untested theoretical concepts. However, most nanomaterials today are phases of matter that are well known and have been studied extensively at the bulk scale. For example, II-VI semiconductors, which are widely studied today at the nanoscale, were employed in photovoltaic applications at the microscale for nearly half a century. The question that arises is whether material processing at the nanoscale can allow us to go beyond the limitations of conventional synthesis techniques? We believe that the next ...


The Optoelectronic Properties Of Surface-Modified Semiconductor Nanocrystal Solids, Earl D. Goodwin Jan 2015

The Optoelectronic Properties Of Surface-Modified Semiconductor Nanocrystal Solids, Earl D. Goodwin

Publicly Accessible Penn Dissertations

Colloidal semiconductor nanocrystals have emerged as fascinating new materials and gained interest in the last 30 years because of their size, shape, and compositionally tunable electronic and optical properties as well as their potential to serve as artificial atoms. Challenges and opportunities have arisen when assembling nanocrystals into nanocrystal solids for electronic and optoelectronic applications, largely because of the significant influence of nanocrystal surface chemistry on the electronic, optical, and structural properties of nanocrystal solids. In order to assemble nanocrystal solids for high performance devices, we must understand and be able to control the effects of nanocrystal surface organic capping ...


Mechanisms Controlling Friction And Adhesion At The Atomic Length-Scale, Xin Zhou Liu Jan 2015

Mechanisms Controlling Friction And Adhesion At The Atomic Length-Scale, Xin Zhou Liu

Publicly Accessible Penn Dissertations

A lack of understanding of the fundamental mechanisms governing atomic-scale adhesion and friction creates ongoing challenges as technologically-relevant devices are miniaturized. One major class of failure mechanisms of such devices results from high friction, adhesion, and wear. This thesis presents investigations into methods by which atomic-scale friction and adhesion can be controlled. Using atomic force microscopy (AFM), friction and adhesion properties of graphene were examined. While friction between the tip and graphene depends on thickness, as explained by the â??puckering effectâ??, adhesion is independent of the thickness when measured conventionally. However, adhesion is transiently higher when measured after the ...


Carbon Nanopipettes For Advanced Cellular Probing And Microinjection, Sean Eric Anderson Jan 2015

Carbon Nanopipettes For Advanced Cellular Probing And Microinjection, Sean Eric Anderson

Publicly Accessible Penn Dissertations

Carbon nanopipettes (CNPs) consist of a pulled-quartz micropipette with a thin layer of amorphous carbon deposited along its entire interior surface via chemical vapor deposition. The micropipette maintains a continuous fluidic pathway from its nanoscopic tip to its distal macroscopic end, while the insulated carbon film provides an electrical path to the tip that can be used as a working electrode. The quartz at the tip of the CNP can be chemically etched to expose a desired length of a carbon pipe to control the size and characteristics of the electrode. CNPs are inexpensive, batch- fabricated, and can be made ...


Engineering A Library Of Anisotropic Building Blocks For Dna-Programmed Colloidal Self-Assembly, James Thomas Mcginley Jan 2015

Engineering A Library Of Anisotropic Building Blocks For Dna-Programmed Colloidal Self-Assembly, James Thomas Mcginley

Publicly Accessible Penn Dissertations

Programmable DNA interactions are an effective and versatile tool in the field of colloidal directed self-assembly. Colloidal systems are programmed by manipulating a variety of tunable parameters, such as particle sizes and DNA interaction strengths, and can self-assemble into a large and growing variety of colloidal crystal and gel structures. Since isotropically-interacting spherical particles generally form close-packed structures, the production and use of building blocks with anisotropic interactions, such as polyhedral particles, colloidal clusters, and patchy colloids, has been a rich research area in recent years.

This work represents a true expansion of the capabilities of DNA-directed colloidal assemblies, and ...


Novel Roles Of Cell Cycle Regulator E2f1 In The Cns: Implications For Synaptic Damage In Hiv-Associated Neurocognitive Disorders, Jenhao Harry Ting Jan 2014

Novel Roles Of Cell Cycle Regulator E2f1 In The Cns: Implications For Synaptic Damage In Hiv-Associated Neurocognitive Disorders, Jenhao Harry Ting

Publicly Accessible Penn Dissertations

HIV-associated neurocognitive disorders (HAND) are comprised of a host of cognitive, motor, and behavioral impairments affecting approximately 30-50% of HIV-infected individuals. Despite the development of combination antiretrovirals as a therapy to suppress viral replication, there is currently no effective treatment for HAND-associated neurological symptoms. Advanced understanding of HAND neuropathogenesis is necessary to identify novel therapeutic targets that mediate the neuronal damage and neuronal death associated with this disease. One of the molecular pathways implicated in HAND progression is the aberrant activation of the cell cycle machinery. Activation of the cell cycle machinery leads to the coordinated disinhibiton of the transcription ...


Local Optoelectronic Properties Of Zinc-Porphyrin/Gold Molecular Interfaces, Xi Chen Jan 2014

Local Optoelectronic Properties Of Zinc-Porphyrin/Gold Molecular Interfaces, Xi Chen

Publicly Accessible Penn Dissertations

This research consists in designing a series of experiments to determine the molecular orbital energy levels of zinc-porphyrin molecule when vertically attached to Au(111) substrate. To study the zinc-porphyrine molecular orbitals we use visible light of different wavelengths. Thiolated zinc-porphyrin oligomer molecules link to Au(111) surface, embedded within an 1-octanethiol self-assembled monolayer. Current-Voltage characterization technique allow us to determine the electronic orbital structures of different zinc-porphyrin oligomer single molecules via scanning tunneling microscope. Coupling lasers of different wavelengths and the tunneling junction, illumination effect on the molecular orbital energy levels of zinc-porphyrin molecules is investigated. The results indicate ...


The Optical Properties Of Spiky Gold Nanoshells, Simon Hastings Jan 2014

The Optical Properties Of Spiky Gold Nanoshells, Simon Hastings

Publicly Accessible Penn Dissertations

Plasmonic nanoparticles are a powerful and versatile tool for molecular sensing, drug delivery, and cancer treatment. When exposed to incident light, these nanoparticles have greatly increased far-field scattering and near-field enhancement. Spiky gold nanoshells are a recently developed class of nanoparticles composed of sharp gold spikes decorating a polystyrene core. Spiky nanoshells are synthesized using the templated surfactant-assisted seed growth method, which enables extensive control of the nanoparticle morphology. Here, it is shown that these particles have a tailorable far-field resonance, extremely uniform single-particle surface enhanced Raman scattering, and modal interference in dark-field microscopy measurements. Finite-difference time-domain simulations are performed ...


Flexible Electronics Based On Solution Processable Organic Semiconductors And Colloidal Semiconductor Nanocrystals, Yuming Lai Jan 2014

Flexible Electronics Based On Solution Processable Organic Semiconductors And Colloidal Semiconductor Nanocrystals, Yuming Lai

Publicly Accessible Penn Dissertations

Solution-processable semiconductors hold great potential for the large-area, low-cost fabrication of flexible electronics. Recent advances in flexible electronics have introduced new functional devices such as light-weight displays and conformal sensors. However, key challenges remain to develop flexible devices from emerging materials that use simple fabrication processes and have high-performance.

In this thesis, we first use a solution-processable organic semiconductor to build field-effect transistors on large-area plastic with mobility of 0.1 cm^2/Vs. Combined with passive components, we are able to build voltage amplifiers to capture few mV amplitude bio-signals. This work provides a proof of concept on applying ...


Designing Nanomaterials For Electronic And Optoelectronic Devices Through Charge Carrier Control, Soong Ju Oh Jan 2014

Designing Nanomaterials For Electronic And Optoelectronic Devices Through Charge Carrier Control, Soong Ju Oh

Publicly Accessible Penn Dissertations

Colloidal semiconductor nanocrystals (NCs) have been shown to be promising materials for electronic and optoelectronic device applications because of their unique size-dependent properties and low-cost solution processability. However, the integration of these materials into devices has been challenging due to a lack of available methods to: 1) accurately control charge carrier statistics, such as majority carrier type and concentration, and carrier mobilities, and 2) efficiently passivate surface defects inherent in NC materials arising from their high surface-volume ratio.

In this thesis, we study the fundamental physics of charge carriers paramount for device application. Then, we introduce several measurement techniques to ...


Shape-Control And Doping Of Lanthanides And Transition Metal Oxide Nanocrystals With Tailored Properties And Their Shape-Directed Self-Assembly, Taejong Paik Jan 2014

Shape-Control And Doping Of Lanthanides And Transition Metal Oxide Nanocrystals With Tailored Properties And Their Shape-Directed Self-Assembly, Taejong Paik

Publicly Accessible Penn Dissertations

Lanthanide and transition metal oxides are widely used in various applications such phosphors, lasers, magnets, and catalysts, and have formed an important platform for biomedical research and clinical medicine. The synthesis of highly uniform nanomaterials with controlled size, shape, and compositions is paramount to precisely understanding their physical properties and to arrange them into highly ordered arrays to design functional metamaterials. Herein, I describe novel chemistry to synthesize highly uniform lanthanide and transition metal oxide nanocrystals. The size, shape, and compositions of lanthanide-based nanocrystals are systematically controlled with the addition of alkali metal salts. The reaction mechanism is investigated to ...


A Novel Needleless Liquid Jet Injection Methodology For Improving Direct Cardiac Gene Delivery: An Optimization Of Parameters, Aav Mediated Therapy And Investigation Of Host Responses In Ischemic Heart Failure, Anthony Samuel Fargnoli Jan 2014

A Novel Needleless Liquid Jet Injection Methodology For Improving Direct Cardiac Gene Delivery: An Optimization Of Parameters, Aav Mediated Therapy And Investigation Of Host Responses In Ischemic Heart Failure, Anthony Samuel Fargnoli

Publicly Accessible Penn Dissertations

Heart disease remains the leading cause of mortality and morbidity worldwide, with 22 million new patients diagnosed annually. Essentially, all present therapies have significant cost burden to the healthcare system, yet fail to increase survival rates. One key employed strategy is the genetic reprogramming of cells to increase contractility via gene therapy, which has advanced to Phase IIb Clinical Trials for advanced heart failure patients. It has been argued that the most significant barrier preventing FDA approval are resolving problems with safe, efficient myocardial delivery, whereby direct injection in the infarct and remote tissue areas is not clinically feasible. Here ...


Approaches To Mitigate Metal Catalyst Deactivation In Solid Oxide Fuel Cell (Sofc) Fuel Electrodes, Lawrence Adijanto Jan 2013

Approaches To Mitigate Metal Catalyst Deactivation In Solid Oxide Fuel Cell (Sofc) Fuel Electrodes, Lawrence Adijanto

Publicly Accessible Penn Dissertations

While Ni/YSZ cermets have been used successfully in SOFCs, they also have several limitations, thus motivating the use of highly conductive ceramics to replace the Ni components in SOFC anodes. Ceramic electrodes are promising for use in SOFC anodes because they are expected to be less susceptible to sintering and coking, be redox stable, and be more tolerant of impurities like sulfur. In this thesis, for catalytic studies, the infiltration procedure has been used to form composites which have greatly simplified the search for the best ceramics for anode applications.

In the development of ceramic fuel electrodes for SOFC ...


Engineering Tunable Plasmonic Nanostructures To Enhance Upconversion Luminescence, Marjan Saboktakin Jan 2013

Engineering Tunable Plasmonic Nanostructures To Enhance Upconversion Luminescence, Marjan Saboktakin

Publicly Accessible Penn Dissertations

Plasmonic nanostructures, which can confine and manipulate light below the diffraction limit, are becoming increasingly important in many areas of optical physics and devices. One of the areas that can greatly benefit from surface-plasmon mediated confinement of optical fields is the enhancement of emission in low quantum yield materials. The resonant wavelength for plasmonic structures used for emission enhancement is either the excitation or emission wavelengths of the luminescent material. Therefore, a key component in designing plasmonic structures used in luminescent enhancement applications is the ability to engineer and tune plasmonic building blocks to create structures resonant at the desired ...


Directed Synthesis And Doping Of Wide Bandgap Semiconducting Oxide Nanocrystals, Thomas Ross Gordon Jan 2013

Directed Synthesis And Doping Of Wide Bandgap Semiconducting Oxide Nanocrystals, Thomas Ross Gordon

Publicly Accessible Penn Dissertations

Wide bandgap semiconducting oxide nanocrystals are a useful class of materials with high stability and numerous useful properties. In the field of catalysis, high surface area oxides are commonly used as catalytic supports and have been found to be photocatalytically active for the production of renewable fuels. Ultra high vacuum studies of single crystals indicate that the surface structure and faceting of oxides dramatically influence their catalytic properties. For plasmonics applications, degenerately doped oxide nanocrystals may act as low-loss substitutes for metals, but little is known regarding the influence of particle shape or assembly on their optical response. With the ...


Hierarchical Assemblies Of Soft Matters From Polymers And Liquid Crystals On Structured Surfaces, Apiradee Honglawan Jan 2013

Hierarchical Assemblies Of Soft Matters From Polymers And Liquid Crystals On Structured Surfaces, Apiradee Honglawan

Publicly Accessible Penn Dissertations

Hierarchical, multifunctional materials hold important keys to numerous advanced technologies, including electronics, optics, and medicine. This thesis encompasses generation of hierarchical structures with novel morphologies and functions through self-assembly directed by lithographically fabricated templates. Here, two soft materials, amphiphilic random copolymers of photopolymerized acryloyl chloride (ranPAC) and smectic-A liquid crystal (SmA-LC) molecule, 4'(5,5,6,6,7,7,8,8,9,9,10,10,11,11,12,12,12-heptadecaflu-orododecyloxy)-biphenyl-4-carboxylic acid ethyl ester, are synthesized as model systems to investigate the governing principles at the topographic surface/interface.

The ranPAC can self-organize into nanomicelles with high regularity and stability ...