A5082958560- Quantum Dots Synthesis And Properties
- Chalcogenide Semiconductor Thin Films
- Perovskite Materials and Applications
- Gold and Silver Nanoparticles Synthesis and Applications
- Copper-based nanomaterials and applications
- Photonic and Optical Devices
- Nanocluster Synthesis and Applications
- Plasmonic and Surface Plasmon Research
- Photonic Crystals and Applications
- Advanced Photocatalysis Techniques
- Solid-state spectroscopy and crystallography
- Semiconductor Quantum Structures and Devices
- 2D Materials and Applications
- Semiconductor materials and devices
- Electronic and Structural Properties of Oxides
- nanoparticles nucleation surface interactions
- Nonlinear Optical Materials Studies
- Metamaterials and Metasurfaces Applications
- Advanced Semiconductor Detectors and Materials
- Molecular Junctions and Nanostructures
- Catalytic Processes in Materials Science
- Optical properties and cooling technologies in crystalline materials
- Nanowire Synthesis and Applications
- Optical Network Technologies
- Advanced Fiber Laser Technologies
Argonne National Laboratory
2016-2025
Center for Nanoscale Materials
2021-2025
National Technical Information Service
2023
Office of Scientific and Technical Information
2023
Johns Hopkins University
2022
Virginia Commonwealth University
2022
Alex's Lemonade Stand Foundation
2019-2021
Purdue University System
2020
University of Pennsylvania
2011-2017
University of Michigan
2013
We report bandlike transport in solution-deposited, CdSe QD thin-films with room temperature field-effect mobilities for electrons of 27 cm(2)/(V s). A concomitant shift and broadening the solid optical absorption compared to that dispersed samples is consistent electron delocalization measured mobilities. Annealing indium contacts allows thermal diffusion doping thin-films, shifting Fermi energy, filling traps, providing access bands. Temperature-dependent measurements show 220 K on a...
Ammonium thiocyanate (NH(4)SCN) is introduced to exchange the long, insulating ligands used in colloidal nanocrystal (NC) synthesis. The short, air-stable, environmentally benign ligand electrostatically stabilizes a variety of semiconductor and metallic NCs polar solvents, allowing solution-based deposition into thin-film NC solids. NH(4)SCN also effective replacing on after their assembly solid state. spectroscopic properties this provide unprecedented insight chemical electronic nature...
Recent synthetic developments have generated intense interest in the use of cesium lead halide perovskite nanocrystals for light‐emitting applications. This work presents photoluminescence (PL) with tunable composition recorded as function temperature from 80 to 550 K. CsPbBr 3 show highest resilience while chloride‐containing samples relatively poorer preservation at elevated temperatures. Thermal cycling experiments that PL loss is largely reversible temperatures below 450 K, but shows...
Synthetic methods produce libraries of colloidal nanocrystals with tunable physical properties by tailoring the nanocrystal size, shape, and composition. Here, we exploit diversity design materials, interfaces, processes to construct all-nanocrystal electronic devices using solution-based processes. Metallic silver semiconducting cadmium selenide are deposited form high-conductivity high-mobility thin-film electrodes channel layers field-effect transistors. Insulating aluminum oxide...
A simple yet efficient method to remove organic ligands from supported nanocrystals is reported for activating uniform catalysts prepared by colloidal synthesis procedures. The relies on a fast thermal treatment in which are quickly removed air, before sintering can cause changes the size and shape of nanocrystals. short at high temperatures found be sufficient systems catalytic reactions. We show that this widely applicable nanostructures different sizes, shapes, compositions. Being rapid...
Abstract The absorption and photoluminescence, both steady‐state time‐resolved, of CsPbX 3 (X = Cl, Br, I) nanocrystals are reported at temperatures ranging from to 300 K. These measurements offer a unique window into the fundamental properties this class materials which is considered promising for light‐emitting detection devices. bandgaps shown increase low high temperature, none examined cesium‐based perovskite exhibit bandgap discontinuity in temperature range suggesting constant crystal...
We report a simple, solution-based, postsynthetic colloidal, atomic layer deposition (PS-cALD) process to engineer stepwise the surface stoichiometry and therefore electronic properties of lead chalcogenide nanocrystal (NC) thin films integrated in devices. found that unlike chalcogen-enriched NC surfaces are structurally, optically, electronically unstable, chloride treatment creates well-passivated shell stabilizes NCs. Using PS-cALD we demonstrate high electron field-effect mobilities...
Significant interest exists in lead trihalides that present the perovskite structure owing to their demonstrated potential photovoltaic, lasing, and display applications. These materials are also notable for unusual phase behavior often displaying easily accessible transitions. In this work, time-resolved X-ray diffraction, performed on cesium bromide nanocrystals, maps lattice response controlled excitation fluence. nanocrystals undergo a reversible, photoinduced orthorhombic-to-cubic...
We present a generalized cation–anion codoping methodology for the synthesis of monodisperse, doped metal-oxide nanocrystals (NCs) that exhibit near-infrared localized surface plasmon resonance (LSPR) with highest reported quality factors. demonstrate that, in addition to use common cation dopants, incorporation fluorine into lattice as an anion dopant can further increase free-carrier concentration within individual NCs; this supports cooperative effects mixed doping shifting LSPR higher...
We study the plasmonic properties of self-assembled binary nanocrystal superlattices (BNSLs) using correlated optical microspectrophotometry and electron microscopy performed on individual BNSL domains. The strength near-field couplings between adjacent nanocrystals (NCs) can be systematically engineered by varying NC size, composition, lattice symmetry BNSLs, leading to broadband spectral tunability collective response BNSLs across entire visible spectrum. Self-assembled multicomponent...
Self-assembly of multicomponent anisotropic nanocrystals with controlled orientation and spatial distribution allows the design novel metamaterials unique shape- orientation-dependent collective properties. Although many phases binary structures are theoretically proposed, examples assemblies, which experimentally realized colloidal nanocrystals, still limited. In this report, we demonstrate formation ternary superlattices from two-dimensional LaF3 nanodisks one-dimensional CdSe/CdS nanorods...
Mixtures of anisotropic nanocrystals promise a great diversity superlattices and phase behaviors beyond those single-component systems. However, obtaining colloidal shape alloy in which two different shapes are thermodynamically coassembled into crystalline superlattice has remained challenge. Here we present joint experimental-computational investigation geometrically ubiquitous nanocrystalline building blocks-nanorods nanospheres-that overcome their natural entropic tendency toward...
Abstract Nonlinear optical responses of materials play a vital role for the development active nanophotonic and plasmonic devices. Optical nonlinearity induced by intense excitation mobile electrons in metallic nanostructures can provide large-amplitude, dynamic tuning their electromagnetic response, which is potentially useful all-optical processing information beam control. Here we report on sub-picosecond indium tin oxide nanorod arrays (ITO-NRAs) following intraband, on-plasmon-resonance...
ADVERTISEMENT RETURN TO ISSUECommunicationNEXTDirect Synthesis of Six-Monolayer (1.9 nm) Thick Zinc-Blende CdSe Nanoplatelets Emitting at 585 nmWooje ChoWooje ChoDepartment Chemistry, University Chicago, Illinois 60637, United StatesMore by Wooje Cho, Siyoung KimSiyoung KimInstitute for Molecular Engineering, Kim, Igor CoropceanuIgor CoropceanuDepartment Coropceanu, Vishwas SrivastavaVishwas SrivastavaDepartment Srivastava, Benjamin T. DirollBenjamin DirollCenter Nanoscale Materials, Argonne...
Carrier multiplication is a process whereby kinetic energy of carrier relaxes via generation additional electron-hole pairs (excitons). This effect has been extensively studied in the context advanced photoconversion as it could boost yield generated excitons. driven by carrier-carrier interactions that lead to excitation valence-band electron conduction band. Normally, rate phonon-assisted relaxation exceeds Coulombic collisions, which limits yield. Here we show this limitation can be...
Transferring nanocrystals (NCs) from the laboratory environment toward practical applications has raised new challenges. HgTe appears as most spectrally tunable infrared colloidal platform. Its low-temperature synthesis reduces growth energy cost yet also favors sintering. Once coupled to a read-out circuit, Joule effect aggregates particles, leading poorly defined optical edge and large dark current. Here, we demonstrate that CdS shells bring expected thermal stability (no redshift upon...
Efficient, fast, and robust scintillators for ionizing radiation detection are crucial in various fields, including medical diagnostics, defense, particle physics. However, traditional scintillator technologies face challenges simultaneously achieving optimal performance high-speed operation. Herein we introduce colloidal quantum shell heterostructures as X-ray electron scintillators, combining efficiency, speed, durability. Quantum shells exhibit light yields up to 70,000 photons MeV
We demonstrate optical metamaterial design using colloidal gold nanocrystal building blocks. In the solid state, chemically exchanging nanocrystals' surface-capping molecules provides a tailorable dielectric-to-metal transition exhibiting 10(10) range in DC conductivity and dielectric permittivity ranging from everywhere positive to negative throughout visible-to-near-IR. Direct, wide-area nanoimprinting of subwavelength superstructures at room temperature, on plastic glass substrates,...
Amplified spontaneous emission (ASE) and lasing from solution-processed materials are demonstrated in the challenging violet-to-blue (430–490 nm) spectral region for colloidal nanoplatelets of CdS newly synthesized core/shell CdS/ZnS nanoplatelets. Despite modest band-edge photoluminescence quantum yields 2% or less single excitons, which we show results hole trapping, samples exhibit low ASE thresholds. Furthermore, four-monolayer at shorter wavelengths than any reported film...