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Full-Text Articles in Nanoscience and Nanotechnology

Irradiation-Induced Nanocluster Evolution, Didier Ishimwe, Matthew J. Swenson, Janelle P. Wharry Aug 2017

Irradiation-Induced Nanocluster Evolution, Didier Ishimwe, Matthew J. Swenson, Janelle P. Wharry

The Summer Undergraduate Research Fellowship (SURF) Symposium

Oxide dispersion strengthened steel (ODS) and commercial ferritic-martensitic (F-M) alloys are widely accepted candidate structural materials for designing advanced nuclear reactors. Nanoclusters embedded in the steel matrix are key microstructural features of both alloy types. Irradiation from nuclear fusion and fission affects the morphology of these nanoparticles, altering the performance of the alloys and potentially decreasing their usable lifetime. Thus, it is important to understand the effect of irradiation on these nanoparticles in order to predict long-term nuclear reactor performance. It was found that the evolution of nanoclusters in each material is different depending on the experimental irradiation parameters. The ...


Optical Sub-Diffraction Limited Focusing For Confined Heating And Lithography, Luis M. Traverso Dec 2016

Optical Sub-Diffraction Limited Focusing For Confined Heating And Lithography, Luis M. Traverso

Open Access Dissertations

Electronics and nanotechnology is constantly demanding a decrease in size of fabricated nanoscale features. This decrease in size has become much more difficult recently due to the limited resolution of optical systems that are fundamental to many nanofabrication methods. A lot of effort has been made to fabricate devices smaller than the diffraction limit of light. Creating devices that are capable of confining fields by means of interference patterns of propagating wave modes and surface plasmon, has proven successful to confine light into smaller spot sizes.

Zone plate diffraction lenses generate spots with dimensions very close to the diffraction limit ...


Performance Of Tf-Vls Grown Inp Photovoltaic Cells, Junyan Shi, Yubo Sun, Peter Bermel Aug 2016

Performance Of Tf-Vls Grown Inp Photovoltaic Cells, Junyan Shi, Yubo Sun, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

A grand challenge of photovoltaics (PV) is to find materials offering a promising combination of low costs and high efficiencies. While III-V material-based PV cells have set many world records, often their cost is much greater than other commercial cells. To help address this gap, thin-film vapor-liquid-solid (TF-VLS) grown Indium Phosphide (InP) PV cells have recently been developed, which both eliminate a key source of high costs and offer a direct bandgap of 1.34eV with potential to approach maximum theoretical efficiencies. However, the unanticipated phenomenon of open circuit voltage (Voc) degradation has prevented TF-VLS grown InP PV cells ...


Thermophotovoltaic System Simulation With Realistic Experimental Considerations, Evan L. Schlenker, Zhiguang Zhou, Peter Bermel Aug 2015

Thermophotovoltaic System Simulation With Realistic Experimental Considerations, Evan L. Schlenker, Zhiguang Zhou, Peter Bermel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermophotovoltaic (TPV) systems are a promising type of energy generation method that convert heat into electricity via thermal radiation. TPV has potential to benefit the economy, the energy sector, and the environment by converting waste heat from other power generation methods into electricity. Simulations of these systems can play a key role in designing TPV systems and validating their experimental performance. Current simulation tools can model important aspects of TPV systems fairly accurately, but generally make certain simplifying assumptions that are challenging to reproduce in experiments. Developing a simulation tool that accurately captures thermal emission and reflection in complex, realistic ...


3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet Aug 2015

3d Printing Nanostructured Thermoelectric Device, Qianru Jia, Collier Miers, Amy Marconnet

The Summer Undergraduate Research Fellowship (SURF) Symposium

Thermoelectric materials convert thermal energy to electrical energy and vice versa. Thermoelectrics have attracted much attention and research efforts due to the possibility solving electronic cooling problems and reducing energy consumption through waste heat recovery. The efficiency of a thermoelectric material is determined by the dimensionless figure of merit ZT, which depends on both thermal and electrical properties. Researchers have worked for several decades to improve the ZT, but there had been little progress until nanomaterials and nanofabrication became widely available. Nanotechnology makes the ZT enhancement attainable by disconnecting the linkage between thermal and electrical transport. Printing customized, flexible thermoelectric ...


Electronic And Mechanical Material Properties From Dft Calculations, Usama Kamran, David Guzman, Alejandro Strachan Aug 2015

Electronic And Mechanical Material Properties From Dft Calculations, Usama Kamran, David Guzman, Alejandro Strachan

The Summer Undergraduate Research Fellowship (SURF) Symposium

Materials modeling provides a cost and time efficient method for studying their properties, especially in nanotechnology where length and time scales are not accessible experimentally. Our research focuses on developing a tool useful for both instructional and research purposes that calculates material properties. The tool relies on density functional theory (DFT) calculations to compute specific properties for a wide range of materials including semiconductors, insulators, and metals. A major goal with our tool was to keep the GUI very simple for novice users, such as students, while retaining an advanced option section for experienced users, such as researchers. The tool ...


Granular Matter: Microstructural Evolution And Mechanical Response, Aashish Ghimire, Ishan Srivastava, Timothy S. Fisher Aug 2014

Granular Matter: Microstructural Evolution And Mechanical Response, Aashish Ghimire, Ishan Srivastava, Timothy S. Fisher

The Summer Undergraduate Research Fellowship (SURF) Symposium

Heterogeneous (nano) composites, manufactured by the densification of variously sized grains, represent an important and ubiquitous class of technologically relevant materials. Typical grain sizes in such materials range from macroscopic to a few nanometers. The morphology exhibited by such disordered materials is complex and intricately connected with its thermal and electrical transport properties. It is important to quantify the geometric features of these materials and simulate the fabrication process. Additionally, granular materials exhibit complex structural and mechanical properties that crucially govern their reliability during industrial use. In this work, we simulate the densification of soft deformable grains from a low-density ...


Thermoelectric (Te) Device Made Using Pbte Nanocrystal Coated Glass Fibers, Xiaoqin Zhu, Scott W. Finefrock, Yue Wu Aug 2014

Thermoelectric (Te) Device Made Using Pbte Nanocrystal Coated Glass Fibers, Xiaoqin Zhu, Scott W. Finefrock, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Around 60 % of the energy produced in the U.S. in 2013 was wasted and most of this was dissipated in the form of heat. Thermoelectric materials could potentially harvest part of the energy being wasted by converting heat energy into electrical energy. Lead telluride nanocrystals are an interesting thermoelectric material particularly for solution-based coating of flexible substrates. The purpose of this project is to develop a working thermoelectric device using p-n pairs of PbTe nanocrystal coated glass fibers. In this project, p- and n- type PbTe nanocrystals are synthesized in solution. Bare glass fibers are sequentially dipped in solutions ...


The Simulation Of Resonant Tunneling Diodes, Woodrow A. Gilbertson, Pengyu Long, Jim Fonseca, Gerhard Klimeck Aug 2014

The Simulation Of Resonant Tunneling Diodes, Woodrow A. Gilbertson, Pengyu Long, Jim Fonseca, Gerhard Klimeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

The goal of this project is to improve the simulation of an electrical device known as a Resonant Tunneling Diode (RTD). Diodes are in most electronic devices today, but RTDs have 10 times greater switching speeds than regular diodes. This increase in efficiency would have impacts from supercomputers to the next big cell phone. The increased functionality of the simulation tool will come from implementing more recent mathematical solvers and modeling techniques. The simulation tool makes use of a variant of Non-Equilibrium Green Functions (NEGF) with an effective mass approximation. The two contacts are treated as equilibrium regions and the ...


Elementary Studies Of Twisted Bilayer Graphene, Branden P. Burns, Yong P. Chen Oct 2013

Elementary Studies Of Twisted Bilayer Graphene, Branden P. Burns, Yong P. Chen

The Summer Undergraduate Research Fellowship (SURF) Symposium

In the nanotechnology field, some existing materials and applications are harmful to the environment, not efficient for certain tasks, or too expensive to be fully utilized. Graphene is a strong and cheap material that can be used to improve current nanotechnologies for more practical uses in society. Twisted bilayer graphene (TBG) is an orientation of graphene layers that exhibit different properties than regular bilayer graphene. It is made by placing a single layer of graphene on top of another at an angle with respect to the other lattice orientation. Understanding the characteristics of TBG is important to uncover more physics ...


Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski Oct 2013

Prism - Materials Simulation Tool, Ryan Widjaja, Marisol Koslowski

The Summer Undergraduate Research Fellowship (SURF) Symposium

MEMS (Micro-electromechanical System) is a combined electrical and mechanical nano-scaled device with rapidly growing applications. We have developed a contacting radio frequency capacitive MEMS that is commonly used as capacitive switches and contact actuators in PRISM (Prediction of Reliability, Integrity and Survivability of Microsystems) lab at Purdue University. Our research team has focused on creating a simulation of MEMS’s survivability towards crazing and cracking. Our particular objective in this project is to create a tool that can help users perform complex quantitative calculations regarding the properties of different materials. This tool will generate various plots visualizing the properties, such ...


Crystalline Cellulose – Atomistic Modeling Toolkit, Mateo Gomez, Pablo Zavattieri Dr. Oct 2013

Crystalline Cellulose – Atomistic Modeling Toolkit, Mateo Gomez, Pablo Zavattieri Dr.

The Summer Undergraduate Research Fellowship (SURF) Symposium

Nature has created efficient strategies to make materials with hierarchical internal structure that often exhibit exceptional mechanical properties. One such example is found in cellulose, in fact it is eight times stronger than stainless steel and advantage is that cellulose incredibly cheap, because processing is obtained from purified wood pulp (it is environmental friendly). The most prevalent modeling technique to study the fundamental mechanical behavior of the crystalline cellulose has been Molecular Dynamics (MD). As a predictive tool, MD allows us to study the behavior of crystalline cellulose at the atomic level, and as such, it accurately predicts the crystalline ...


Synthesizing Bismuth Telluride Nanowires In A Large Scale And Investigating The Energy Filtering Effect By Blending Bismuth Telluride Nanowires And Silver Nanoparticle In Thermoelectrics, Henka Darsono, Haiyu Fang, Yue Wu Oct 2013

Synthesizing Bismuth Telluride Nanowires In A Large Scale And Investigating The Energy Filtering Effect By Blending Bismuth Telluride Nanowires And Silver Nanoparticle In Thermoelectrics, Henka Darsono, Haiyu Fang, Yue Wu

The Summer Undergraduate Research Fellowship (SURF) Symposium

More than 50% of the energy sources becomes “waste” energy generally dissipated to the atmosphere in the form of heat. Thermoelectric effect is a conversion of temperature difference to electric voltage and can be used to convert the wasted heat to useful work. Nanomaterials have great potentials in the field of thermoelectric effect since they have properties that can allow higher efficiency in converting this wasted heat to electricity as compared to bulk materials. The purpose of this project is to develop a method to synthesize bismuth telluride (Bi2Te3) nanowires on a large scale and incorporate nanoinclusions ...


Small-Scale Solutions To Grand Challenges In Thermal Management, Suresh V. Garimella Nov 2010

Small-Scale Solutions To Grand Challenges In Thermal Management, Suresh V. Garimella

Birck and NCN Publications

Research needs in the field of thermal management of microelectronics and microsystems are identified, followed by a brief discussion of recent advances in solution approaches. These include novel solutions that rely on two-phase flow at the microscale, micropumps, droplet actuation on structured surfaces, passive transport in wick structures, ion-driven and piezoelectrically driven airflow, nanostructured thermal materials, and novel diagnostic tools.


Vertical Carbon Nanotube Devices With Nanoscale Lengths Controlled Without Lithography, Aaron D. Franklin, Robert A. Sayer, Timothy D. Sands, David B. Janes, Timothy S. Fisher Jul 2009

Vertical Carbon Nanotube Devices With Nanoscale Lengths Controlled Without Lithography, Aaron D. Franklin, Robert A. Sayer, Timothy D. Sands, David B. Janes, Timothy S. Fisher

PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems

Vertical single-walled carbon nanotubes (vSWCNTs) are synthesized within highly ordered porous anodic alumina (PAA) templates supported on Si substrates. A process for obtaining thin-film PAA with long-range ordered nanopores is presented in this paper. Each nanopore contains at most one v-SWCNT that is supported by a dielectric and addressed by electrochemically formed Pd nanowire source contacts and evaporated Pd drain contacts. Characteristics of these completely vertical, two-terminal nanotube devices are presented. Control of the v-SWCNT length is demonstrated using a straightforward etching process with lengths of less than 100 nm achieved without the need for complex/expensive lithography. This effective ...