Microstructure And Property Evaluation Of Lifepo4 Thin Films For Application In Microbatteries, 2010 University of Texas at El Paso
Microstructure And Property Evaluation Of Lifepo4 Thin Films For Application In Microbatteries, Jose Marcos Mares
Open Access Theses & Dissertations
The shortage of fossil fuels and the requirements to produce clean, environmental friendly, efficient, and economical energy are the principal problems in the context of energy technology for current and future generations. Therefore, advanced energy storage and conversion capabilities with higher capacity and efficiency are desired. Currently, there is an enormous interest in the development of high energy density rechargeable batteries for use in domestic applications, automotive industries and portable electronic applications. The present research focuses on the development of LiFePO4 thin films for solid-state thin-film microbatteries. The present effort was performed with a specific purpose of understanding the effect …
A New Green Chemistry Method Based On Plant Extracts To Synthesize Gold Nanoparticles, 2010 University of Texas at El Paso
A New Green Chemistry Method Based On Plant Extracts To Synthesize Gold Nanoparticles, Milka Odemariz Montes Castillo
Open Access Theses & Dissertations
Extraordinary chemical and physical properties exhibited by nanomaterials, as compared to their bulk counterparts, have made the area of nanotechnology a growing realm in the past three decades. It is the nanoscale size (from 1 to 100 nm) and the morphologies of nanomaterials that provide several properties and applications not possible for the same material in the bulk. Magnetic and optical properties, as well as surface reactivity are highly dependent on the size and morphology of the nanomaterial. Diverse nanomaterials are being widely used in molecular diagnostics as well as in medicine, electronic and optical devices. Among the most studied …
Development Of Wide Band Gap Semiconductor Materials For Renewable Energy, 2010 University of Texas at El Paso
Development Of Wide Band Gap Semiconductor Materials For Renewable Energy, S.M. Sarif Masud
Open Access Theses & Dissertations
Several new wide band gap semiconductor nanocomposite photocatalytic materials have been synthesized from HTiNbO5 and HNb3O8 for solar energy conversion. As a source of renewable energy, the materials are being tested to produce hydrogen fuel from water via photolysis. The materials have high surface areas, are macroporous, and have flatband potentials suitable for reducing water to create hydrogen. Under visible or ultra violet light, the materials were found to be very promising as hydrogen evolving photocatalysts. As part of the synthesis of the composites, the catalysts also exhibited excellent catalytic activity under UV light for reducing ionic platinum and gold …
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, 2010 Purdue University - Main Campus
Reactive Molecular Dynamics: Numerical Methods And Algorithmic Techniques, Hasan Metin Aktulga, Shailaja Pandit, Adri C. T. Van Duin, Ananth Y. Grama
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
Modeling atomic and molecular systems requires computation-intensive quantum mechanical methods such as, but not limited to, density functional theory (DFT) [11]. These methods have been successful in predicting various properties of chemical systems at atomistic detail. Due to the inherent nonlocality of quantum mechanics, the scalability of these methods ranges from O(N3) to O(N7) depending on the method used and approximations involved. This significantly limits the size of simulated systems to a few thousands of atoms, even on large scale parallel platforms. On the other hand, classical approximations of quantum systems, although computationally (relatively) easy to implement, yield simpler models …
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, 2010 Purdue University - Main Campus
Unusual Scaling Obsrvations In The Quality Factors Of Cantilevered Carbon Nanotube Resonators, Ajit K. Vallabhaneni, Jeffrey F. Rhoads, Xiulin Ruan, Jayathi Y. Murthy
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
This work examines the quality factors (Q factors) of resonance associated with the axial and transverse vibrations of single-wall carbon nanotube (SWCNT) resonators through the use of molecular dynamics (MD) simulation. Specifically, the work investigates the effect of device length, diameter, and chirality, as well as temperature, on the resonant frequency and quality factor of these devices, and benchmarks the results of MD simulation against classical theories of energy dissipation. Of note are the facts that the quality factors associated with transverse vibration decrease with increasing device diameter and are largely insensitive to chirality. Additionally, quality factors increase with increasing …
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, 2010 Purdue University - Main Campus
A Viscoelastic-Aware Experimentally-Derived Model For Analog Rf Mems Varactors, Hao-Han Hsu, Dimitrios Peroulis
PRISM: NNSA Center for Prediction of Reliability, Integrity and Survivability of Microsystems
In this paper we present, for the ¯rst time, an experimentally-extracted model for the spring con- stant and tuning range of an analog RF-MEMS var- actor that includes viscoelastic e®ects in RF-MEMS devices. By utilizing a bi-state bias condition with one state lasting 60 minutes and the other 1 minute, this model focuses on capturing the true electrome- chanical behavior of the varactor. An experimental setup with very high long-term accuracy is created to measure capacitance of the varactor up to 1,370 hours. The impact of these e®ects and the e®ective- ness of the model are demonstrated on a tunable- …
Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions, 2010 Purdue University
Quantum Approach To Electronic Noise Calculations In The Presence Of Electron-Phonon Interactions, Hong-Hyun Park, Gerhard Klimeck
Birck and NCN Publications
A quantum-mechanical approach to the calculation of electronic noise for nanoscale devices is presented. This method is based on the nonequilibrium Green’s-function formalism with electron-phonon scattering mechanisms and takes the effects of the Pauli exclusion principle and the long-range Coulomb interactions into account. As examples the drain current noise characteristics of silicon nanowire transistors at room temperature are simulated. The drain current noise in the saturation regime is primarily shot-noise dominant but is suppressed for higher gate biases due to the electron-electron correlation in the channel region. The role of electron-phonon interactions on noise, the transition from thermal to shot …
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients, 2010 Electrical and Computer Engineering, Purdue University
On Landauer Versus Boltzmann And Full Band Versus Effective Mass Evaluation Of Thermoelectric Transport Coefficients, Changwook Jeong, Raseong Kim, Mathieu Luisier, Supriyo Datta, Mark S. Lundstrom
Birck and NCN Publications
Using a full band description of electronic bandstructure, the Landauer approach to diffusive transport is mathematically related to the solution of the Boltzmann transport equation, and expressions for the thermoelectric parameters in both formalisms are presented. Quantum mechanical and semiclassical techniques to obtain from a full description of the bandstructure, E(k), the density of modes in the Landauer approach or the transport distribution in the Boltzmann solution are compared and thermoelectric transport coefficients are evaluated. Several example calculations for representative bulk materials are presented and the full band results are related to the more common effective mass formalism. Finally, given …
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids, 2010 Purdue University
Accurate Force Spectroscopy In Tapping Mode Atomic Force Microscopy In Liquids, Xin Xu, John Melcher, Arvind Raman
Birck and NCN Publications
Existing force spectroscopy methods in tapping mode atomic force microscopy (AFM) such as higher harmonic inversion [M. Stark, R. W. Stark, W. M. Heckl, and R. Guckenberger, Proc. Natl. Acad. Sci. U. S. A. 99, 8473 (2002)] or scanning probe acceleration microscopy [J. Legleiter, M. Park, B. Cusick, and T. Kowalewski, Proc. Natl. Acad. Sci. U. S. A. 103, 4813 (2006)] or integral relations [M. Lee and W. Jhe, Phys. Rev. Lett. 97, 036104 (2006); S. Hu and A. Raman, Nanotechnology 19, 375704 (2008); H. Holscher, Appl. Phys. Lett. 89, 123109 (2006); A. J. Katan, Nanotechnology 20, 165703 (2009)] require …
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, 2010 Purdue University - Main Campus
Theory Of ‘Selectivity’ Of Label-Free Nanobiosensors – A Geometro-Physical Perspective, Pradeep R. Nair, Muhammad A. Alam
Birck and NCN Publications
Modern label-free biosensors are generally far more sensitive and require orders of magnitude less incubation time compared to their classical counterparts. However, a more important characteristic regarding the viability of this technology for applications in Genomics/Proteomics is defined by the ‘Selectivity’, i.e., the ability to concurrently and uniquely detect multiple target biomolecules in the presence of interfering species. Currently, there is no theory of Selectivity that allows optimization of competing factors and there are few experiments to probe this problem systematically. In this article, we use the elementary considerations of surface exclusion, diffusion limited transport, and void distribution function to …
Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, 2010 University of Nevada, Las Vegas
Giant Raman Enhancement On Nanoporous Gold Film By Conjugating With Nanoparticles For Single-Molecule Detection, Lihua Qian, Biswajit Das, Yan Li, Zhilin Yang
Electrical & Computer Engineering Faculty Research
Hot spots have the contradictively geometrical requirements for both the narrowest interstices to provide strong near-field coupling, and sufficient space to allow entrance of the analytes. Herein, a two-step method is employed to create hot spots within hybrid nanostructures, which consist of self-supported nanoporous gold films with the absorbed probes and subsequent nanoparticle conjugates without surface agents or mechanical motion. The molecules confined into 1 nm interstice exhibit 2.9 × 107 times enhancement in Raman scattering compared to pure nanoporous gold. Giant enhancement primarily results from strong near-field coupling between nanopore and nanoparticle, which is theoretically confirmed by finite-difference …
On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field, 2010 University of Nevada, Las Vegas
On The Effect Of Hydrodynamic Slip On The Polarization Of A Nonconducting Spherical Particle In An Alternating Electric Field, Hui Zhao
Mechanical Engineering Faculty Research
The polarization of a charged, dielectric, spherical particle with a hydrodynamically slipping surface under the influence of a uniform alternating electric field is studied by solving the standard model (the Poisson–Nernst–Planck equations). The dipole moment characterizing the strength of the polarization is computed as a function of the double layer thickness, the electric field frequency, the particle’s surface charge, and the slip length. Our studies reveal that two processes contribute to the dipole moment: ion transport inside the double layer driven by the electric field and the particle’s electrophoretic motion. The hydrodynamic slip will simultaneously impact both processes. In the …
Nano-Scaled Fet Device For Cmos Technology, 2010 North Carolina Agricultural and Technical State University
Nano-Scaled Fet Device For Cmos Technology, Prabhat Ranjan Pathak
Dissertations
In this work the 3-D structure of the Accumulation mode (ACM) and Enhance mode (ECM) FinFET was developed by the Taurus-Device Editor. The design of both ACM and ECM FinFET was optimized for high-performance IC applications to meet ITRS specification for Ioff current, for 9nm gate length. The design of ACM and ECM FinFET is optimized, analyzed and compared against each other with respect to Darin Induced Barrier Lower (DIBL), Sub-threshold Swing(SS), operation and performance characteristics with varying electrical and physical parameters Silicon thickness (Tsi), Source/Drain doping gradient (σsd), electrical channel length (Leff ), …
Luminescence Enhancement Of Cdte Nanostructures In Laf3:Ce/Cdte Nanocomposites, 2010 University of Texas at Arlington
Luminescence Enhancement Of Cdte Nanostructures In Laf3:Ce/Cdte Nanocomposites, Mingzhen Yao, Xing Zhang, Lun Ma, Wei Chen, Alan G. Joly, Jinsong Huang, Qingwu Wang
Department of Mechanical and Materials Engineering: Faculty Publications
Radiation detection demands new scintillators with high quantum efficiency, high energy resolution, and short luminescence lifetimes. Nanocomposites consisting of quantum dots and Ce3+ doped nanophosphors may be able to meet these requirements. Here, we report the luminescence enhancement of LaF3:Ce/CdTe nanocomposites which were synthesized by a wet chemistry method. CdTe quantum dots in LaF3:Ce/CdTe nanocomposites are converted into nanowires, while in LaF3 /CdTe nanocomposites no such conversion is observed. As a result, the CdTe luminescence in LaF3:Ce/CdTe nanocomposites is enhanced about five times, while in LaF3 /CdTe nanocomposites no enhancement was …
Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), 2010 Wayne State University
Synthetic Levers Enabling Control Of Phase, Size And Morphology In Transition Metal Phosphide Nanoparticles (Fe, Ni), Elayaraja Muthuswamy
Wayne State University Dissertations
ABSTRACT
SYNTHETIC LEVERS ENABLING CONTROL OF PHASE, SIZE AND MORPHOLOGY IN TRANSITION METAL PHOSPHIDE NANOPARTICLES (FE, NI)
by
ELAYARAJA MUTHUSWAMY
May 2011
Advisor:Dr. Stephanie L. Brock
Major: Chemistry
Degree: Doctor of Philosophy
This dissertation study focuses on (1) development of a synthetic strategy to control phase in nanoscale iron phosphides; (2) extension of the developed phase control strategy to the nanoscale nickel phosphide system with simultaneous control on size and morphology and (3) illustration of the enhanced reactivity of nanoscale oxide systems.
A synthetic strategy to control phase in nanoscale iron phosphides was developed to prepare phase-pure samples of …
Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, 2010 College of William & Mary - Arts & Sciences
Silver-Polyimide Nanocomposite Films: Single-Stage Synthesis And Analysis Of Metalized Partially-Fluorinated Polyimide Btda/4-Bdaf Prepared From Silver(I) Complexes, Joshua Erold Robert Abelard
Dissertations, Theses, and Masters Projects
No abstract provided.
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, 2010 Technological University Dublin
Selective Solubilisation Of Single Walled Carbon Nanotubes Using Polycyclic Aromatic Hydrocarbons, Sourabhi Debnath
Doctoral
Single-walled carbon nanotubes (SWCNTS) are proposed to be one of the most promising nanomaterials, with unique electronic and mechanical properties which lend themselves to a variety of applications. In all cases the quality of the SWCNT material is important, and for some applications it is paramount. Despite sustained efforts, all currently known SWCNT synthetic techniques generate significant quantities of impurities. They also grow in bundles or ropes and are largely insoluble in common organic solvents. SWCNTS can have a range of structures and their electronic properties (metallic or semiconducting) depend on their structure and as well on their diameters. Currently …
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, 2010 Old Dominion University
Dielectrophoretic Choking Phenomenon In A Converging-Diverging Microchannel, Ye Ai, Shizhi Qian, Sheng Liu, Sang W. Joo
Mechanical & Aerospace Engineering Faculty Publications
Experiments show that particles smaller than the throat size of converging-diverging microchannels can sometimes be trapped near the throat. This critical phenomenon is associated with the negative dc dielectrophoresis arising from nonuniform electric fields in the microchannels. A finite-element model, accounting for the particle-fluid-electric field interactions, is employed to investigate the conditions for this dielectrophoretic (DEP) choking in a converging-diverging microchannel for the first time. It is shown quantitatively that the DEP choking occurs for high nonuniformity of electric fields, high ratio of particle size to throat size, and high ratio of particle's zeta potential to that of microchannel. © …
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion, 2010 University of South Carolina - Columbia
Far-Field Optical Nanoscopy Based On Continuous Wave Laser Stimulated Emission Depletion, C. Kuang, Wei Zhao, Guiren Wang
Faculty Publications
Stimulated emission depletion (STED) microscopy is one of the breakthrough technologies that belong to far-field optical microscopy and can achieve nanoscale spatial resolution. We demonstrate a far-field optical nanoscopy based on continuous wave lasers with different wavelengths, i.e., violet and green lasers for excitation and STED, respectively. Fluorescent dyes Coumarin 102 and Atto 390 are used for validating the depletion efficiency. Fluorescent nanoparticles are selected for characterizing the spatial resolution of the STED system. Linear scanning of the laser beams of the STED system along one line of a microscope slide, which is coated with the nanoparticles, indicates that a …
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, 2009 University of Pennsylvania
Super-High-Frequency Two-Port Aln Contour-Mode Resonators For Rf Applications, Matteo Rinaldi, Chiara Zuniga, Chengjie Zuo, Gianluca Piazza
Matteo Rinaldi
This paper reports on the design and experimental verification of a new class of thin-film (250 nm) super-high-frequency laterally-vibrating piezoelectric microelectromechanical (MEMS) resonators suitable for the fabrication of narrow-band MEMS filters operating at frequencies above 3 GHz. The device dimensions have been opportunely scaled both in the lateral and vertical dimensions to excite a contour-extensional mode of vibration in nanofeatures of an ultra-thin (250 nm) AlN film. In this first demonstration, 2-port resonators vibrating up to 4.5 GHz have been fabricated on the same die and attained electromechanical coupling, kt2, in excess of 1.5%. These devices are employed to synthesize …