A5073701259- nanoparticles nucleation surface interactions
- Metal and Thin Film Mechanics
- Semiconductor materials and interfaces
- Electronic and Structural Properties of Oxides
- Advanced Materials Characterization Techniques
- Advanced ceramic materials synthesis
- Catalytic Processes in Materials Science
- Electron and X-Ray Spectroscopy Techniques
- Solidification and crystal growth phenomena
- Force Microscopy Techniques and Applications
- ZnO doping and properties
- Microstructure and mechanical properties
- Semiconductor materials and devices
- Surface and Thin Film Phenomena
- GaN-based semiconductor devices and materials
- Diamond and Carbon-based Materials Research
- Ion-surface interactions and analysis
- Advancements in Battery Materials
- Metallurgical Processes and Thermodynamics
- Semiconductor Quantum Structures and Devices
- Physics of Superconductivity and Magnetism
- Advancements in Solid Oxide Fuel Cells
- Fluid Dynamics and Thin Films
- Silicon Nanostructures and Photoluminescence
- Mesoporous Materials and Catalysis
University of Connecticut
2013-2024
Center for Integrated Nanotechnologies
2014-2024
Sandia National Laboratories
2014-2024
University of Minnesota
2000-2009
University of Minnesota System
1994-2007
Twin Cities Orthopedics
2002-2006
Sandia National Laboratories California
1995-2005
American Ceramic Society
1992-2001
Minot State University
1999
Innovative Scientific Solutions (United States)
1999
We combine CdSe semiconductor nanocrystals (or quantum dots) and single-crystal ZnO nanowires to demonstrate a new type of quantum-dot-sensitized solar cell. An array was grown vertically from fluorine-doped tin oxide conducting substrate. dots, capped with mercaptopropionic acid, were attached the surface nanowires. When illuminated visible light, excited dots injected electrons across dot-nanowire interface. The morphology then provided photoinjected direct electrical pathway photoanode....
Introduction.- Some History.- What You Already Know.- Bonds and Energy Bonds.- Models, Crystals Chemistry.- Binary Compounds.- Complex Crystal Glass Structures.- Equilibrium Phase Diagrams.- Furnaces.- Characterizing Structure, Defects Point Defects, Charge Diffusion.- Are Dislocations Unimportant?- Surfaces, Nanoparticles Foams.- Interfaces in Polycrystals.- Boundaries, Particles Pores.- Mechanical Testing.- Deforming: Plastic.- Fracturing: Brittleness.- Raw Materials.- Powders, Fibers,...
Carbon nanotubes produced in arcs have been found to the form of multiwalled fullerenes, at least over short lengths. Sintering tubes each other is predominant source defects that limit utility these otherwise perfect fullerene structures. The use a water-cooled copper cathode minimized such defects, permitting longer than 40 micrometers be attached macroscopic electrodes and extracted from bulk deposit. A detailed mechanism features high electric field (and field-emission from) open...
A novel dual-plasma system has been developed to combine the synthesis of silicon nanocrystals (Si-NCs), etching controllably tailor Si-NC size, and surface functionalization Si-NCs into one simple all-gas-phase process. are synthesized in SiH4-based plasma; they then travel through CF4-based plasma, where etched passivated by C F. The resulting exhibit air-stable emission across full visible spectrum. Structural optical characterization indicates that red-to-green range is based on...
We employed an in situ electrochemical cell the transmission electron microscope (TEM) together with ex time-of-flight, secondary-ion mass spectrometry (TOF-SIMS) depth profiling, and FIB–helium ion scanning (HIM) imaging to detail structural compositional changes associated Na/Na+ charging/discharging of 50 100 nm thin films Sb. TOF-SIMS on a partially sodiated Sb film gives Na signal that progressively decreases toward current collector, indicating sodiation does not proceed uniformly....
Individual nanoparticles of silicon and titanium having diameters in the range $40--140\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$ have been repeatedly compressed by a nanoindenter. Even at low loads, small tip-particle particle-substrate contacts generate extreme pressures within confined particle, influencing its stiffness fracture toughness. The effect these high on measured modulus is taken into account invoking Murnaghan equation-of-state-based analysis. Fracture toughness particles found...
Designing biodegradable scaffolds with bone-compatible mechanical properties has been a significant challenge in the field of bone tissue engineering and regenerative engineering. The objective this work is to improve polymeric scaffold's strength by compositing it mechanically superior carbon nanotubes. Poly(lactide-co-glycolide) (PLGA) microsphere exhibit range human cancellous bone. On other hand, nanotubes have outstanding properties. aim study further PLGA such that they may be...
This paper presents general methods of preparing three-dimensionally ordered macroporous (3DOM) metals or alloys via templated precipitation and subsequent chemical conversion metal salts (acetates, oxalates) within colloidal crystals poly(methyl methacrylate) (PMMA) polystyrene (PS) spheres. Three approaches are given to prepare 3DOM metallic Ni, Co, Fe the alloy Ni1-xCox: (1) calcination oxalate/template composite in a nitrogen atmosphere, (2) formation oxide followed by reduction...
Single-crystal nanoparticles of silicon, several tens nanometres in diameter, may be suitable as building blocks for single-nanoparticle electronic devices. Previous studies produced low-pressure plasmas have demonstrated the synthesis nanocrystals 2–10 nm diameter but larger particles were amorphous or polycrystalline. This work reports use a constricted, filamentary capacitively coupled plasma to produce single-crystal silicon with diameters between 20 and 80 nm. Particles are highly...
Single-crystal nanoparticles of silicon, several tens nm in diameter, may be suitable as building blocks for single-nanoparticle electronic devices. Previous studies produced low-pressure plasmas have demonstrated the synthesis nanocrystals 2–10 diameter but larger particles were amorphous or polycrystalline. This work reports use an inductively coupled plasma to produce single-crystal silicon with diameters between 20 and 80 nm. Electron microscopy confirm that are highly oriented...
Catalysts are required for both the oxidation of water and reduction oxygen. Blended oxides Ir Ru superior whereas mixtures Pt perform better when oxygen on same electrode. A strategy rationing these elements is explored by formation a thin film using dry, flame process. IrxPt1-xO2-y IrxRu1-xO2-y were deposited from vapor phase, as films, onto substrates glassy carbon, polypropylene, quartz. Elemental analysis Ir-Pt electrode suggests stoichiometry Ir0.56Pt0.44O2-y. Bulk diffraction shows...
The morphology of surfaces several ceramic materials has been examined using transmission electron microscopy. approach used was to prepare a sample for examination in the microscope, carefully clean it, and then heat‐treat it. In case oxides studied (alumina spinel) samples were heated air; non‐oxides (α‐SiC β ‐SiC) annealed under vacuum. all but one such that surface faceted parallel nearest low‐index plane give well‐defined terraces; these separated by ledges which also tended facet...
Using a new technique in forming the cubic single-crystal silicon nanoparticles that are about 40 nm on side, authors have demonstrated vertical-flow surround-gate Schottky-barrier transistor. This approach allows use of well-known approaches to surface passivation and contact formation within context deposited materials for device applications. It opens door novel three-dimensional integrated circuits hyper integration. The fabrication process involves successive deposition planarization...