A5027146586- 2D Materials and Applications
- Graphene research and applications
- Topological Materials and Phenomena
- Advanced Thermoelectric Materials and Devices
- MXene and MAX Phase Materials
- Inorganic Chemistry and Materials
- Ga2O3 and related materials
- Magnetic and transport properties of perovskites and related materials
- Electronic and Structural Properties of Oxides
- Nanowire Synthesis and Applications
- Supramolecular Self-Assembly in Materials
- Crystallization and Solubility Studies
- X-ray Diffraction in Crystallography
- Chalcogenide Semiconductor Thin Films
- Perovskite Materials and Applications
- Advanced Condensed Matter Physics
- Iron-based superconductors research
- ZnO doping and properties
- Magnetic properties of thin films
- Heusler alloys: electronic and magnetic properties
- Thermal properties of materials
- Multiferroics and related materials
- GaN-based semiconductor devices and materials
- Machine Learning in Materials Science
- Particle physics theoretical and experimental studies
The Ohio State University
2016-2025
Max Planck Institute for Chemical Physics of Solids
2023-2024
Stanford University
2021
Northwestern University
2008-2016
Center for Innovation
2014
Pennsylvania State University
2013
Xerox (France)
2013
Berkeley College
2007-2010
University of California, Berkeley
2003-2007
Lawrence Berkeley National Laboratory
2003-2007
Homogeneous and dense arrays of ZnO nanowires were synthesized on silicon wafers (and many other substrates) using a mild solution process at 90 °C. Uniform nanocrystals deposited to act as seeds for subsequent hydrothermal nanowire growth, which yielded single-crystalline grown along the [0001] direction oriented perpendicular wafer surface (see picture; scale bar=1μm). The photoluminescence lasing behavior has been studied function annealing treatment conditions.
A method for growing vertical ZnO nanowire arrays on arbitrary substrates using either gas-phase or solution-phase approaches is presented. approximately 10 nm-thick layer of textured nanocrystals with their c axes normal to the substrate formed by decomposition zinc acetate at 200-350 degrees C provide nucleation sites growth. The nanorod made in solution have a rod diameter, length, density, and orientation desirable use ordered nanorod-polymer solar cells.
▪ Abstract Semiconductor nanowires and nanotubes exhibit novel electronic optical properties owing to their unique structural one-dimensionality possible quantum confinement effects in two dimensions. With a broad selection of compositions band structures, these one-dimensional semiconductor nanostructures are considered be the critical components wide range potential nanoscale device applications. To fully exploit nanostructures, current research has focused on rational synthetic control...
Langmuir−Blodgett technique was used to assemble monolayers (with areas over 20 cm2) of aligned silver nanowires that are ∼50 nm in diameter and 2−3 μm length. These possess pentagonal cross-sections pyramidal tips. They close-packed parallel each other. The resulting nanowire serve as excellent substrates for surface-enhanced Raman spectroscopy (SERS) with large electromagnetic field enhancement factors (2 × 105 thiol 2,4-dinitrotoluene, 2 109 Rhodamine 6G) can readily be ultrasensitive,...
Graphene's success has shown not only that it is possible to create stable, single-atom-thick sheets from a crystalline solid but these materials have fundamentally different properties than the parent material. We synthesized for first time, millimeter-scale crystals of hydrogen-terminated germanium multilayered graphane analogue (germanane, GeH) topochemical deintercalation CaGe2. This layered van der Waals analogous (CH). The surface layer GeH slowly oxidizes in air over span 5 months,...
Although the electrical integration of chemically synthesized nanowires has been achieved with lithography, optical integration, which promises high speeds and greater device versatility, remains unexplored. We describe properties functions individual crystalline oxide nanoribbons that act as subwavelength waveguides assess their applicability nanoscale photonic elements. The length, flexibility, strength these structures enable manipulation on surfaces, including linking nanoribbon other...
Silicon nanowires have received considerable attention as transistor components because they represent a facile route toward sub-100-nm single-crystalline Si features. Herein we demonstrate the direct vertical integration of nanowire arrays into surrounding gate field effect transistors without need for postgrowth assembly processes. The device fabrication allows channel diameters to be readily reduced 5-nm regime. These first-generation vertically integrated (VINFETs) exhibit electronic...
We lay the foundation for determining microscopic spin interactions in two-dimensional (2D) ferromagnets by combining angle-dependent ferromagnetic resonance (FMR) experiments on high quality CrI$_3$ single crystals with theoretical modeling based symmetries. discover that Kitaev interaction is strongest this material $K \sim -5.2$ meV, 25 times larger than Heisenberg exchange $J -0.2$ and responsible opening $\sim$5 meV gap at Dirac points spin-wave dispersion. Furthermore, we find...
High-quality gallium nitride nanowires have been synthesized via metal-initiated metalorganic chemical vapor deposition for the first time. Excellent substrate coverage was observed wires prepared on silicon, c-plane, and a-plane sapphire substrates. The were formed vapor−liquid−solid mechanism with gold, iron, or nickel as growth initiators found to widths of 15-200 nm. Transmission electron microscopy confirmed that single-crystalline oriented predominantly along [210] [110] direction....
Quantum wire lasers are generally fabricated through complex overgrowth processes with molecular beam epitaxy. The material systems of such overgrown quantum wires have been limited to Al−Ga−As−P, which leads emission largely in the visible region. We describe a simple, one-step chemical vapor deposition process for making based on Al−Ga−N system. A novel quantum-wire-in-optical-fiber (Qwof) nanostructure was obtained as result spontaneous phase separation at nanometer scale one dimension....
We report real-time high temperature transmission electron microscopy observations of the growth GaN nanowires via a self-catalytic vapor−liquid−solid (VLS) mechanism. High thermal decomposition in vacuum yields nanoscale Ga liquid droplets and gallium/nitrogen vapor species for subsequent nanowire nucleation growth. This is first direct observation VLS mechanism suggests new strategies synthesizing electronically pure single-crystalline semiconductor nanowires.
The creation of smart, self-assembling materials that undergo morphological transitions in response to specific physiological environments can allow for the enhanced accumulation imaging or drug delivery agents based on differences diffusion kinetics. Here, we have developed a series peptide amphiphile molecules transform either isolated from spherical micelles into nanofibers when pH is slightly reduced 7.4 6.6, isotonic salt solutions simulate acidic extracellular microenvironment...