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Publicly Accessible Penn Dissertations

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Full-Text Articles in Nanoscience and Nanotechnology

Alternating Multiblock Polyethylenes With Associating Groups: Self-Assembled Nanoscale Morphologies And Ion Transport, Lu Yan Jan 2019

Alternating Multiblock Polyethylenes With Associating Groups: Self-Assembled Nanoscale Morphologies And Ion Transport, Lu Yan

Publicly Accessible Penn Dissertations

Single-ion conductors based on block copolymers (BCPs) are promising solid-state electrolytes for energy storage systems. Their ability to self-assemble into distinct nanostructures can provide both high ion transference numbers and strong mechanical integrity. Connecting the microphase-separated morphologies to the ion transport properties in BCP electrolytes as well as designing polymers to produce specific ion-conducting domain remain a critically important challenge.

Combining non-conducting polyethylene (PE) blocks that alternate with short strongly-interacting ionic blocks leads to a wide range of intriguing nanoscale phase-separated morphologies. Depending on the PE block lengths, these alternating multiblock copolymers exhibit amorphous or semicrystalline morphologies and their ionic ...


Designing Colloidal Nanomaterials For Electronic And Optoelectronic Devices Through Surface Modification, Tianshuo Zhao Jan 2019

Designing Colloidal Nanomaterials For Electronic And Optoelectronic Devices Through Surface Modification, Tianshuo Zhao

Publicly Accessible Penn Dissertations

Colloidal quantum dots (QDs) are nanometer-sized semiconductors synthesized by wet chemical methods and stabilized by surface ligands in solvents. They are prized for the size-dependent electronic band structures, giving rise to tunable optical properties. Their solution form is also suitable for large-area and low-cost fabrication processes. These unique characteristics make this class of materials promising as building blocks for next-generation thin-film electronic and optoelectronic devices. However, the construction of QD based devices requires precise control of their material properties, including carrier mobility, lifetime, doping concentration and energy positions of the conduction and valence band edges. The large surface-to-volume ratio allows ...


Alignment And Morphological Effects Of Nanoplates In Lamellar Diblock Copolymer Thin Films, Nadia Krook Jan 2019

Alignment And Morphological Effects Of Nanoplates In Lamellar Diblock Copolymer Thin Films, Nadia Krook

Publicly Accessible Penn Dissertations

The ability to disperse inorganic nanoparticles (NPs) of various shapes, sizes, and compositions in polymeric matrices enables researchers to continuously engineer new material combinations with different resulting properties. Polymer nanocomposites (PNCs) can be further customized for specific applications by intentionally organizing and orienting NPs within these hybrid materials. Despite significant advances in the field of PNCs, full control over the orientation of embedded anisotropic NPs, specifically nanoplates, is not well-established without employing multistep processes. Capturing either in-plane (parallel) or out-of-plane (vertical) orientation of nanoplates in thin polymer films through a scalable method would create new opportunities for developing coating technologies ...


Engineering Novel Nanomaterials From Ultrasmall Gold Clusters For Use In Cancer Therapy, Elizabeth Marie Higbee Dempsey Jan 2019

Engineering Novel Nanomaterials From Ultrasmall Gold Clusters For Use In Cancer Therapy, Elizabeth Marie Higbee Dempsey

Publicly Accessible Penn Dissertations

One of the biggest hurdles in clinical therapy is ensuring that drugs have appropriate pharmacokinetic profiles; they must traffic to sites of interest and accumulate there at relevant concentrations, but must also be eliminated from tissues at a desirable rate. This is especially important in oncology because precise tumor locations may be unknown and therapeutics are often toxic to off-target healthy tissues. Nanoscale drug formulations provide a useful way to modulate and improve the behavior of drugs within biological systems. For example, gold nanoparticles (AuNPs) can be designed with physiochemical properties that allow them to traffic from the bloodstream into ...


The Role Of Mentalizing In Information Propagation, Elisa C. Baek Jan 2019

The Role Of Mentalizing In Information Propagation, Elisa C. Baek

Publicly Accessible Penn Dissertations

What are the psychological drivers that lead to successful information propagation between communicators and receivers of shared messages? What factors lead communicators to share information with others, and receivers to be successfully influenced by the information? The current dissertation focuses on the role of mentalizing, or considering other people’s mental states, as one factor that leads to successful information propagation between communicators and receivers. Study 1 of this dissertation focused on the role of mentalizing in communicators of influence and provided behavioral evidence suggesting that mentalizing causally increases communicators’ likelihood to share information. Specifically, instructing information sharers to consider ...


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 ...


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 ...


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 ...


Optical Modeling And Analysis Of Disordered Plasmonic Nanoparticle Ensembles, Chen Li Jan 2017

Optical Modeling And Analysis Of Disordered Plasmonic Nanoparticle Ensembles, Chen Li

Publicly Accessible Penn Dissertations

Plasmonic nanoparticle synthesis provids a facile and cost-effective bottom-up solution to fabrication of nanoscaled structures. With effective packaging methods like embedding into polymer composites and superlattice assemblies, the chemically synthesized nanoparticles are promising candidates for functional devices. However, compared with precisely patterned surfaces commonly used for device fabrication, the structural inhomogenity and disorder in nanoparticle ensembles give rise to challenge in their characterization using conventional methods and in turn, their application. This work aims to develop models as guideline to design facile characterization methods that can be used to effectively describe the properties of disordered plasmonic nanoparticle ensembles. Two types ...


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 ...


Engineering Plasmonic Nanocrystal Coupling Through Template-Assisted Self-Assembly, Nicholas J. Greybush Jan 2017

Engineering Plasmonic Nanocrystal Coupling Through Template-Assisted Self-Assembly, Nicholas J. Greybush

Publicly Accessible Penn Dissertations

The construction of materials from nanocrystal building blocks represents a powerful new paradigm for materials design. Just as nature’s materials orchestrate intricate combinations of atoms from the library of the periodic table, nanocrystal “metamaterials” integrate individual nanocrystals into larger architectures with emergent collective properties. The individual nanocrystal “meta-atoms” that make up these materials are themselves each a nanoscale atomic system with tailorable size, shape, and elemental composition, enabling the creation of hierarchical materials with predesigned structure at multiple length scales. However, an improved fundamental understanding of the interactions among individual nanocrystals is needed in order to translate this structural ...


Designing Plasmonic Materials And Optical Metasurfaces For Light Manipulation And Optical Sensing, Wenxiang Chen Jan 2017

Designing Plasmonic Materials And Optical Metasurfaces For Light Manipulation And Optical Sensing, Wenxiang Chen

Publicly Accessible Penn Dissertations

Metamaterials are artificial materials designed to create optical properties that do not exist in nature. They are assemblies of subwavelength structures that are tailored in size, shape, composition, and orientation to realize the desired property. Metamaterials are promising for applications in diverse areas: optical filters, lenses, holography, sensors, photodetectors, photovoltaics, photocatalysts, medical devices, and many more, because of their excellent abilities in bending, absorbing, enhancing and blocking light. However, the practical use of metamaterials is challenged by the lack of plasmonic materials with proper permittivity for different applications and the slow and expensive fabrication methods available to pattern sub-wavelength structures ...


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 ...


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 ...


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 ...


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 ...


Adhesion And Wear Of Nanoscale Polymer Contacts, Yijie Jiang Jan 2017

Adhesion And Wear Of Nanoscale Polymer Contacts, Yijie Jiang

Publicly Accessible Penn Dissertations

Atomic force microscopy (AFM) is a powerful tool for high resolution surface measurements, nanolithography, and tip-based nanomanufacturing. An understanding of the nanoscale tribological behavior of the tip-sample contact, including adhesion and wear, is critical in these applications. In this dissertation, the adhesion and wear of polymethyl methacrylate (PMMA) in contact with an ultrananocrystalline diamond (UNCD) AFM tip is investigated using a combination of AFM-based nanomechanics experiments and finite element analysis (FEA).

A novel AFM-based method, which combines pull-off force measurements and characterization of the 3D geometry of AFM tip, was developed to quantify the properties of the adhesive traction-separation relationship ...


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 ...


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 ...


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 ...


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 ...


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 ...


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 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 ...


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 ...


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 ...


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 ...