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Portland State University

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Full-Text Articles in Nanoscience and Nanotechnology

Carbon-Supported Transition Metal Nanoparticles For Catalytic And Electromagnetic Applications, Kavita Meduri Nov 2018

Carbon-Supported Transition Metal Nanoparticles For Catalytic And Electromagnetic Applications, Kavita Meduri

Dissertations and Theses

Recently, there has been growing interest in using transition metals (TM) for catalytic and electromagnetic applications, due to the ability of TMs to form stable compounds in multiple oxidation states. In this research, the focus has been on the synthesis and characterization of carbon-supported TM nanoparticles (NPs), specifically palladium (Pd) and gold (Au) NPs, for catalytic applications, and transition metal oxides (TMO) NPs, specifically Fe3O4 NPs for electromagnetic applications. Carbon supports have several advantages, such as enabling even distribution of particles, offering large specific surface area with excellent electron conductivity, and relative chemical inertness.

In this dissertation ...


Investigation Of The Acoustic Response Of A Confined Mesoscopic Water Film Utilizing A Combined Atomic Force Microscope And Shear Force Microscope Technique, Monte Allen Kozell Jul 2018

Investigation Of The Acoustic Response Of A Confined Mesoscopic Water Film Utilizing A Combined Atomic Force Microscope And Shear Force Microscope Technique, Monte Allen Kozell

Dissertations and Theses

An atomic force microscopy beam-like cantilever is combined with an electrical tuning fork to form a shear force probe that is capable of generating an acoustic response from the mesoscopic water layer under ambient conditions while simultaneously monitoring force applied in the normal direction and the electrical response of the tuning fork shear force probe. Two shear force probes were designed and fabricated. A gallium ion beam was used to deposit carbon as a probe material. The carbon probe material was characterized using energy dispersive x-ray spectroscopy and scanning transmission electron microscopy. The probes were experimentally validated by demonstrating the ...


Binder Free Graphene Hybridized Fe3o4 Nanoparticles For Supercapacitor Applications, Nathan D. Jansen May 2018

Binder Free Graphene Hybridized Fe3o4 Nanoparticles For Supercapacitor Applications, Nathan D. Jansen

Undergraduate Research & Mentoring Program

In a world with increasing energy demands, the need for safe and mobile energy storage grows. There are a number of renewable energy sources that can be harvested, however peak demand and peak production times tend to not overlap. As the capabilities of collecting the energy grows so does the need to store the energy for later consumption. The two promising methods of storing energy are batteries or supercapacitors. Both technologies employ an electrode consisting of an active material bound to a current collector. This material participates in a redox reaction, storing charge electrochemically to later be used as energy ...


Development Of A Liquid Contacting Method For Investigating Photovoltaic Properties Of Pbs Quantum Dot Solids, Vitalii Alekseevich Dereviankin Feb 2018

Development Of A Liquid Contacting Method For Investigating Photovoltaic Properties Of Pbs Quantum Dot Solids, Vitalii Alekseevich Dereviankin

Dissertations and Theses

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photon-to-electron conversion yields. However, record power conversion efficiencies remain limited mainly due to bulk and interfacial defects in the light absorbing material (QD solids). Interfacial defects can be formed when a semiconductor, such as QD solid, is contacted by another material and may predetermine the semiconductor/metal or semiconductor/metal-oxide junction properties. The objective of the work described in this dissertation was set to explore whether electrochemical contacting using liquid electrolytes can provide sufficient means of contacting the QD solids to investigate their PV performance without introducing the ...


Aerobic Method For The Synthesis Of Nearly Size-Monodisperse Bismuth Nanoparticles From A Redox Non-Innocent Precursor, Hayden Winter, Elena Christopher-Allison, Anna L. Brown, Andrea M. Goforth Feb 2018

Aerobic Method For The Synthesis Of Nearly Size-Monodisperse Bismuth Nanoparticles From A Redox Non-Innocent Precursor, Hayden Winter, Elena Christopher-Allison, Anna L. Brown, Andrea M. Goforth

Chemistry Faculty Publications and Presentations

Herein, we report an aerobic synthesis method to produce bismuth nanoparticles (Bi NPs) with average diameters in the range 40-80 nm using commercially available bismuth triiodide (BiI3) as starting material; the method uses only readily available chemicals and conventional laboratory equipment. Furthermore, size data from replicates of the synthesis under standard reaction conditions indicate that this method is highly reproducible in achieving Bi NP populations with low standard deviations in the mean diameters. We also investigated the mechanism of the reaction, which we determined results from the reduction of a soluble alkylammonium iodobismuthate precursor species formed in situ. Under ...


Investigation Into Effects Of Instability And Reactivity Of Hydride-Passivated Silicon Nanoparticles On Interband Photoluminescence, Christine Marie Radlinger May 2017

Investigation Into Effects Of Instability And Reactivity Of Hydride-Passivated Silicon Nanoparticles On Interband Photoluminescence, Christine Marie Radlinger

Dissertations and Theses

While silicon has long been utilized for its electronic properties, its use as an optical material has largely been limited due to the poor efficiency of interband transitions. However, discovery of visible photoluminescence (PL) from nanocrystalline silicon in 1990 triggered many ensuing research efforts to optimize PL from nanocrystalline silicon for optical applications. Currently, use of photoluminescent silicon nanoparticles (Si NPs) is commercially limited by: 1) the instability of the energy and intensity of the PL, and 2) the low quantum yield of interband PL from Si NPs.

Herein, red-emitting, hydrogen-passivated silicon nanoparticles (H-Si NPs) were synthesized by thermally-induced disproportionation ...


Find, Build, And Export Information For 3d Printing Of Your Favorite Molecules And Crystal Structures At Two Dedicated Websites, Paul R. Destefano, Peter Moeck May 2017

Find, Build, And Export Information For 3d Printing Of Your Favorite Molecules And Crystal Structures At Two Dedicated Websites, Paul R. Destefano, Peter Moeck

Student Research Symposium

As 3D printers require instructions, the Nano-Crystallography Group at Portland State University is creating two websites (http://nanocrystallography.org/3dconvert/ and http://nanocrystallography.research.pdx.edu/3d-print-files/convert/) where such instructions are created, interactively, for the atomic arrangements of virtually all known molecules and crystals.

We will prepare a "pipeline" into which crystallographic information enters from two curated open access crystallographic databases, is manipulated to create the desired 3D models, and then is exported in either STL format (the standard for monochrome 3D printing) or VRML/X3D (the ISO successor to STL). The two aforementioned databases are the North-American mirror ...


Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson May 2017

Understanding Photovoltaic Properties Of Pbs Quantum Dot Solids Via Solution Contacting, Vitalii Dereviankin, Erik Johansson

Student Research Symposium

Photovoltaic (PV) devices based on PbS quantum dot (QD) solids demonstrate high photontoelectron conversion yields. However, record power conversion efficiency remain low, in part due to small photovoltages, which in turn are affected by both bulk and interfacial defects. Their relative impacts on limiting the photovoltaic performance of QD solids are not known. Interfacial defects can be formed when contacting a semiconductor and may dominate the semiconductor/metal or metaloxide junction properties. The objective of this study is to explore whether electrochemical contacting using liquid electrolytes provides means of contacting QD solids without introducing interfacial defects. We have initially focused ...


Architectures And Algorithms For Intrinsic Computation With Memristive Devices, Jens Bûrger Aug 2016

Architectures And Algorithms For Intrinsic Computation With Memristive Devices, Jens Bûrger

Dissertations and Theses

Neuromorphic engineering is the research field dedicated to the study and design of brain-inspired hardware and software tools. Recent advances in emerging nanoelectronics promote the implementation of synaptic connections based on memristive devices. Their non-volatile modifiable conductance was shown to exhibit the synaptic properties often used in connecting and training neural layers. With their nanoscale size and non-volatile memory property, they promise a next step in designing more area and energy efficient neuromorphic hardware.

My research deals with the challenges of harnessing memristive device properties that go beyond the behaviors utilized for synaptic weight storage. Based on devices that exhibit ...


Expanding The Versatility Of Nano Assembled Capsules As Platform Of Potential High Payload Mri Contrast Agents, Annah Farashishiko Jul 2016

Expanding The Versatility Of Nano Assembled Capsules As Platform Of Potential High Payload Mri Contrast Agents, Annah Farashishiko

Dissertations and Theses

Magnetic resonance imaging (MRI) has become a powerful clinical modality in diagnostic medicine. It is non-invasive and offers high spatial and temporal resolution. The goal of molecular imaging is to reveal the pathophysiology underlying the observed anatomy and diagnose diseases. The detection of pathological biomarkers can lead to early recognition of diseases and improved monitoring for recurrence. Clinically available contrast agents are limited in their discrimination of contrast between tissues and they tend to have very high detection limits. Because biomarkers are very low in concentration there is a need for high payload deposition of contrast agent (CA) and targeted ...


Frequency Multiplication In Silicon Nanowires, Marius Mugurel Ghita Jul 2016

Frequency Multiplication In Silicon Nanowires, Marius Mugurel Ghita

Dissertations and Theses

Frequency multiplication is an effect that arises in electronic components that exhibit a non-linear response to electromagnetic stimuli. Barriers to achieving very high frequency response from electronic devices are the device capacitance and other parasitic effects such as resistances that arise from the device geometry and are in general a function of the size of the device. In general, smaller device geometries and features lead to a faster response to electromagnetic stimuli. It was posited that the small size of the silicon nanowires (SiNWs) would lead to small device capacitance and spreading resistance, thus making the silicon nanowires useful in ...


Complete Design Methodology Of A Massively Parallel And Pipelined Memristive Stateful Imply Logic Based Reconfigurable Architecture, Kamela Choudhury Rahman Jun 2016

Complete Design Methodology Of A Massively Parallel And Pipelined Memristive Stateful Imply Logic Based Reconfigurable Architecture, Kamela Choudhury Rahman

Dissertations and Theses

Continued dimensional scaling of CMOS processes is approaching fundamental limits and therefore, alternate new devices and microarchitectures are explored to address the growing need of area scaling and performance gain. New nanotechnologies, such as memristors, emerge. Memristors can be used to perform stateful logic with nanowire crossbars, which allows for implementation of very large binary networks that can be easily reconfigured. This research involves the design of a memristor-based massively parallel datapath for various applications, specifically SIMD (Single Instruction Multiple Data) like architecture, and parallel pipelines. The dissertation develops a new model of massively parallel memristor-CMOS hybrid datapath architectures at ...


One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran Feb 2016

One-Dimensional Nanostructure And Sensing Applications: Tin Dioxide Nanowires And Carbon Nanotubes, Hoang Anh Tran

Dissertations and Theses

The key challenge for a nanomaterial based sensor is how to synthesize in bulk quantity and fabricate an actual device with insightful understanding of operational mechanisms during performance. I report here effective, controllable methods that exploit the concepts of the "green approach" to synthesize two different one-dimensional nanostructures, including tin oxide nanowires and carbon nanotubes. The syntheses are followed by product characterization and sensing device fabrications as well as sensor performance understanding at the molecular level. Sensor-analyte response and recovery kinetics are also presented.

The first part of the thesis describes bulk-scale synthesis and characterization of tin oxide nanowires by ...


Photoluminescent Silicon Nanoparticles: Fluorescent Cellular Imaging Applications And Photoluminescence (Pl) Behavior Study, Sheng-Kuei Chiu Aug 2015

Photoluminescent Silicon Nanoparticles: Fluorescent Cellular Imaging Applications And Photoluminescence (Pl) Behavior Study, Sheng-Kuei Chiu

Dissertations and Theses

Molecular fluorophores and semiconductor quantum dots (QDs) have been used as cellular imaging agents for biomedical research, but each class has challenges associated with their use, including poor photostability or toxicity. Silicon is a semiconductor material that is inexpensive and relatively environmental benign in comparison to heavy metal-containing quantum dots. Thus, red-emitting silicon nanoparticles (Si NPs) are desirable to prepare for cellular imaging application to be used in place of more toxic QDs. However, Si NPs currently suffer poorly understood photoinstability, and furthermore, the origin of the PL remains under debate.

This dissertation first describes the use of diatomaceous earth ...


Optical Properties Of Nanostructured Dielectric Coatings, Brandon Giatti Aug 2014

Optical Properties Of Nanostructured Dielectric Coatings, Brandon Giatti

Dissertations and Theses

Solar cells have extrinsic losses from a variety of sources which can be minimized by optimization of the design and fabrication processes. Reflection from the front surface is one such loss mechanism and has been managed in the past with the usage of planar antireflection coatings. While effective, these coatings are each limited to a single wavelength of light and do not account for varying incident angles of the incoming light source. Three-dimensional nanostructures have shown the ability to inhibit reflection for differing wavelengths and angles of incidence. Nanocones were modeled and show a broadband, multi-angled reflectance decrease due to ...


Zno Nanosheet Arrays Constructed On Weaved Titanium Wire For Cds-Sensitized Solar Cells, Cuncun Wu, Lin Wei, Yitan Li, Chang Liu, Jun Jiao, Yanxue Chen, Liangmo Mei Mar 2014

Zno Nanosheet Arrays Constructed On Weaved Titanium Wire For Cds-Sensitized Solar Cells, Cuncun Wu, Lin Wei, Yitan Li, Chang Liu, Jun Jiao, Yanxue Chen, Liangmo Mei

Mechanical and Materials Engineering Faculty Publications and Presentations

Ordered ZnO nanosheet arrays were grown on weaved titanium wires by a low-temperature hydrothermal method. CdS nanoparticles were deposited onto the ZnO nanosheet arrays using the successive ionic layer adsorption and reaction method to make a photoanode. Nanoparticle-sensitized solar cells were assembled using these CdS/ZnO nanostructured photoanodes, and their photovoltaic performance was studied systematically. The best light-to-electricity conversion efficiency was obtained to be 2.17% under 100 mW/cm/cm2 illumination, and a remarkable shortcircuit photocurrent density of approximately 20.1 mA/cm2 was recorded, which could attribute to the relatively direct pathways for transportation of electrons ...


Cds Quantum Dot-Sensitized Solar Cells Based On Nano-Branched Tio2 Arrays, Chang Liu, Yitan Li, Lin Wei, Cuncun Wu, Yanxue Chen, Liangmo Mei, Jun Jiao Mar 2014

Cds Quantum Dot-Sensitized Solar Cells Based On Nano-Branched Tio2 Arrays, Chang Liu, Yitan Li, Lin Wei, Cuncun Wu, Yanxue Chen, Liangmo Mei, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

Nano-branched rutile TiO2 nanorod arrays were grown on F:SnO2 conductive glass (FTO) by a facile, two-step wet chemical synthesis process at low temperature. The length of the nanobranches was tailored by controlling the growth time, after which CdS quantum dots were deposited on the nano-branched TiO2 arrays using the successive ionic layer adsorption and reaction method to make a photoanode for quantum dot-sensitized solar cells (QDSCs). The photovoltaic properties of the CdS-sensitized nano-branched TiO2 solar cells were studied systematically. A short-circuit current intensity of approximately 7 mA/cm2 and a light-to-electricity conversion efficiency of 0.95% were recorded for ...


Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith Jan 2014

Project Nano: Will Allowing High School Students To Use Research Grade Scanning Electron Microscopes Increase Their Interest In Science?, Leslie Teneyck Smith

Dissertations and Theses

In this study, one AP Biology curriculum unit and one general Biology curriculum unit that included tabletop Scanning Electron Microscope (SEM) technology provided by Project NANO, a grant-funded, collaborative initiative designed to integrate cutting-edge nanotechnology into high school classrooms were implemented at a public high school in rural Oregon. Nine students participated in the AP unit and 52 students participated in the general Biology unit. Each student completed an opinion-based pre and post survey to determine if using the SEM as a part of the curriculum unit had an impact on his or her interest in science or in nanoscience ...


3d Printing Of Crystallographic Models And Open Access Databases, Werner Kaminsky, Trevor J. Snyder, Peter Moeck Jan 2014

3d Printing Of Crystallographic Models And Open Access Databases, Werner Kaminsky, Trevor J. Snyder, Peter Moeck

Physics Faculty Publications and Presentations

Provides a brief overview of opportunities for crystallography allowed by the recent developments in 3D printing technology. in combination with open access databases.


3d Printing & Open Access Databases For Crystallographic College Education, Peter Moeck, Jennifer Stone-Sundberg, Trevor J. Snyder, Werner Kaminsky, Saulius Grazulis, International Advisory Board Of The Crystallography Open Database Jan 2014

3d Printing & Open Access Databases For Crystallographic College Education, Peter Moeck, Jennifer Stone-Sundberg, Trevor J. Snyder, Werner Kaminsky, Saulius Grazulis, International Advisory Board Of The Crystallography Open Database

Physics Faculty Publications and Presentations

Presentation gives an overview of available open access databases of crystals and crystal structures, as well as discussions of how newly developed 3D printing technologies can be used to teach crystallography at the college level. Offers advice regarding conversion of crystallographic information files to 3D printing files, and shares news from the 3D printing of crystallographic models community.


3d Printing Of Crystallographic Models For Interdisciplinary College Education, Peter Moeck, Werner Kaminsky, Trevor J. Snyder Jan 2014

3d Printing Of Crystallographic Models For Interdisciplinary College Education, Peter Moeck, Werner Kaminsky, Trevor J. Snyder

Physics Faculty Publications and Presentations

Provides a brief overview of the Crystallography Open Database, and how advances in 3D printing have created opportunities in teaching of college level crystallography courses.


Negotiating The Inclusion Of Nanoscience Content And Technology In Science Curriculum: An Examination Of Secondary Teachers' Thinking In A Professional Development Project, Jennifer Gayle Wells Oct 2013

Negotiating The Inclusion Of Nanoscience Content And Technology In Science Curriculum: An Examination Of Secondary Teachers' Thinking In A Professional Development Project, Jennifer Gayle Wells

Dissertations and Theses

The Next Generation Science Standards represent a significant challenge for K-12 school reform in the United States in the science, technology, engineering and mathematics (STEM) disciplines (NSTA, 2012). One important difference between the National Science Education Standards (NRC, 1996) and the Next Generation Science Standards (Achieve, 2013) is the more extensive inclusion of nanoscale science and technology. Teacher PD is a key vehicle for implementing this STEM education reform effort (NRC, 2012; Smith, 2001).

The context of this dissertation study is Project Nanoscience and Nanotechnology Outreach (NANO), a secondary level professional development program for teachers that provides a summer workshop ...


Crystallite Phase And Orientation Determinations Of (Mn, Ga) As/Gaas-Crystallites Using Analyzed (Precession) Electron Diffraction Patterns, Ines Häusler, Stavros Nicolopoulos, Edgar F. Rauch, K. Volz, Peter Moeck Jan 2011

Crystallite Phase And Orientation Determinations Of (Mn, Ga) As/Gaas-Crystallites Using Analyzed (Precession) Electron Diffraction Patterns, Ines Häusler, Stavros Nicolopoulos, Edgar F. Rauch, K. Volz, Peter Moeck

Physics Faculty Publications and Presentations

Outline of the presentation:

1. Material system: (Mn,Ga)As/GaAs-crystallites

2. Structure analysis using Nano-beam Diffraction (NBD) Precession Electron Diffraction Technique (PED) --> Structure type I + II

3. Phase and orientation mapping using ASTAR

4. Conclusion


Automated Nanocrystal Orientation And Phase Mapping In The Transmission Electron Microscope On The Basis Of Precession Electron Diffraction, Edgar F. Rauch, Joaquin Portillo, Stavros Nicolopoulos, Daniel Bultreys, Sergei Rouvimov, Peter Moeck Mar 2010

Automated Nanocrystal Orientation And Phase Mapping In The Transmission Electron Microscope On The Basis Of Precession Electron Diffraction, Edgar F. Rauch, Joaquin Portillo, Stavros Nicolopoulos, Daniel Bultreys, Sergei Rouvimov, Peter Moeck

Physics Faculty Publications and Presentations

An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope is described. It is primarily based on the projected reciprocal lattice geometry that is extracted from electron diffraction spot patterns. Precession electron diffraction patterns are especially useful for this purpose. The required hardware allows for a scanning-precession movement of the primary electron beam on the crystalline sample and can be interfaced to any older or newer mid-voltage transmission electron microscope (TEM). Experimentally obtained crystal phase and orientation maps are shown for a variety of samples. Comprehensive commercial and open-access crystallographic databases may be used ...


Automated Crystal Phase And Orientation Mapping Of Nanocrystals In A Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov, Edgar F. Rauch, Stavros Nicolopoulos May 2009

Automated Crystal Phase And Orientation Mapping Of Nanocrystals In A Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov, Edgar F. Rauch, Stavros Nicolopoulos

Physics Faculty Publications and Presentations

An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope (TEM) is described. It is based on the projected reciprocal lattice geometry that is extracted from electron diffraction spot patterns. The required hardware allows for a scanning‐precession movement of the primary electron beam on the crystalline sample and can be interfaced to any newer or older TEM. The software that goes with this hardware is flexible in its intake of raw data so that it can also create orientation and phase maps of nanocrystal from high resolution TEM (HRTEM) images. When the nanocrystals ...


Nanometrology Device Standards For Scanning Probe Mmicroscopes And Processes For Their Fabrication And Use, Peter Moeck Jan 2009

Nanometrology Device Standards For Scanning Probe Mmicroscopes And Processes For Their Fabrication And Use, Peter Moeck

Physics Faculty Publications and Presentations

Nanometrology device standards and methods for fabricating and using such devices in conjunction With scanning probe microscopes are described. The fabrication methods comprise: (1) epitaxial growth that produces nanometer sized islands of knoWn morphology, structural, morphological and chemical stability in typical nanometrology environments, and large height-to-width nano-island aspect ratios, and (2) marking suitable crystallographic directions on the device for alignment With a scanning direction.


Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov Jan 2009

Precession Electron Diffraction And Its Advantages For Structural Fingerprinting In The Transmission Electron Microscope, Peter Moeck, Sergei Rouvimov

Physics Faculty Publications and Presentations

The foundations of precession electron diffraction in a transmission electron microscope are outlined. A brief illustration of the fact that laboratory-based powder X-ray diffraction fingerprinting is not feasible for nanocrystals is given. A procedure for structural fingerprinting of nanocrystals on the basis of structural data that can be extracted from precession electron diffraction spot patterns is proposed.


Structural Identification Of Cubic Iron-Oxide Nanocrystal Mixtures: X-Ray Powder Diffraction Versus Quasi-Kinematic Transmission Electron Microscopy, Peter Moeck Mar 2008

Structural Identification Of Cubic Iron-Oxide Nanocrystal Mixtures: X-Ray Powder Diffraction Versus Quasi-Kinematic Transmission Electron Microscopy, Peter Moeck

Physics Faculty Publications and Presentations

Two novel (and proprietary) strategies for the structural identification of a nanocrystal from either a single high-resolution (HR) transmission electron microscopy (TEM) image or a single precession electron diffraction pattern are proposed and their advantages discussed in comparison to structural fingerprinting from powder X-ray diffraction patterns. Simulations for cubic magnetite and maghemite nanocrystals are used as examples.


Three-Dimensional Structure Of Cdx (X= Se, Te) Nanocrystals By Total X-Ray Diffraction, S. K. Pradhan, Z. T. Deng, F. Tang, Y. Ren, Peter Moeck, V. Petkov Jan 2007

Three-Dimensional Structure Of Cdx (X= Se, Te) Nanocrystals By Total X-Ray Diffraction, S. K. Pradhan, Z. T. Deng, F. Tang, Y. Ren, Peter Moeck, V. Petkov

Physics Faculty Publications and Presentations

The three-dimensional structure of oleic acid-capped CdSe and thiol-capped CdTe nanocrystals used as quantum dots has been determined by total synchrotron radiationx-ray diffraction and atomic pair distribution function analysis. Both CdSe and CdTe are found to exhibit the zinc-blende-type atomic ordering. It is only slightly distorted in CdSe implying the presence of nanosize domains and very heavily distorted in CdTe due to the presence of distinct core-shell regions. The results well demonstrate the great potential of the experimental approach and thus encourage its wider application in quantum dot research.


Transmission Electron Goniometry And Its Relation To Electron Tomography For Materials Science Apoplications, Peter Moeck, P. Fraundorf Nov 2006

Transmission Electron Goniometry And Its Relation To Electron Tomography For Materials Science Apoplications, Peter Moeck, P. Fraundorf

Physics Faculty Publications and Presentations

Aspects of transmission electron goniometry are discussed. Combined with high resolution phase contrast transmission electron microscopy (HRTEM) and atomic resolution scanning TEM (STEM) in the atomic number contrast (Z-STEM) or the phase contrast bright field mode, transmission electron goniometry offers the opportunity to develop dedicated methods for the crystallographic characterization of nanocrystals in three dimensions. The relationship between transmission electron goniometry and electron tomography for materials science applications is briefly discussed. Internet based java applets that facilitate the application of transmission electron goniometry for cubic crystals with calibrated tilt-rotation and double-tilt specimen holders/goniometers are mentioned. The so called cubic-minimalistic ...