scholarly journals Defects and impurities in colloidal Ga2O3 nanocrystals: new opportunities for photonics and lighting

2021 ◽  
pp. 1-8
Author(s):  
Khue Nguyen ◽  
Pavle V. Radovanovic
Keyword(s):  
Visible Spectral Region ◽  
Structure And Properties ◽  
Photoluminescence Properties ◽  
Native Defects ◽  
Optical Glasses ◽  
Reduced Dimensions ◽  
Donor And Acceptor ◽  
Nanocrystal Synthesis ◽  
New Applications ◽  
Significant Attention

Defects, both native and extrinsic, critically determine functional properties of metal oxides. Gallium oxide has recently gained significant attention for its promise in microelectronics, owing to the unique combination of conductivity and high breakdown voltage, and solid-state lighting, owing to the strong photoluminescence in the visible spectral region. These properties are associated with the presence of native defects that can form both donor and acceptor states in Ga2O3. Recently, Ga2O3 nanocrystal synthesis in solution and optical glasses has been developed, allowing for a range of new applications in photonics, lighting, and photocatalysis. This review focuses on the structure and properties of Ga2O3 nanocrystals with a particular emphasis on the electronic structure and interaction of defects in reduced dimensions and their role in the observed photoluminescence properties. In addition to native defects, the effect of selected external impurities, including lanthanide and aliovalent dopants, and alloying on the emission properties of Ga2O3 nanocrystals are also discussed.

Hierarchical Structure and Properties of Graphene Oxide Papers

2013 ◽  
Vol 80 (4) ◽  
Author(s):  
Charles D. Wood ◽  
Marc J. Palmeri ◽  
Karl W. Putz ◽  
Zhi An ◽  
SonBinh T. Nguyen ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Graphene Oxide ◽  
Structural Feature ◽  
Uniaxial Tension ◽  
Hierarchical Structure ◽  
Mechanical Response ◽  
Structure And Properties ◽  
Fracture Surfaces ◽  
High Stiffness ◽  
Significant Attention

The mechanical properties of graphene oxide papers have attracted significant attention in recent years due to their high stiffness and tough behavior. While the structural feature most commonly characterized is the nanosheet spacing, there is a hierarchical structure, which is likely responsible for the impressive mechanical properties. In this paper, we examine the structure of graphene oxide papers on several length scales using novel techniques to distinguish between lamellae and a newly defined feature, termed “super-lamellae.” The differentiation between these intermediate features provides context to the previously observed mechanical response and fracture surfaces of graphene oxide papers, particularly under uniaxial tension.

Study on the Effect of Fe3O4 Nanoparticle Dopants on the Properties of Magneto Optical Glasses

2011 ◽  
Vol 213 ◽  
pp. 330-333 ◽  
Author(s):  
Qiu Ling Chen ◽  
Wan Lin ◽  
Qiu Ling Chen ◽  
Shuang Bao Wang
Keyword(s):  
Faraday Rotation ◽  
Fe3o4 Nanoparticles ◽  
Optical Glass ◽  
Alkaline Media ◽  
Structure And Properties ◽  
Fe3o4 Nanoparticle ◽  
X Ray Diffraction ◽  
X Ray ◽  
Optical Glasses ◽  
Doped Glasses

Fe3O4 nanoparticles doped magnetic-optical PbO-Bi2O3-B2O3 glasses were prepared and studied and the effects of Fe3O4 nanoparticle on the properties of magnetic-optical glass were analyzed. It is found that the doping of Fe3O4 nanoparticles into glasses increased the Verdet constant of magneto optical glass without evident degradation in glass transmittance. The formation of Fe3O4 nanoparticles was obtained through coprecipitation of Fe(II) and Fe(III) in alkaline media. The structure and properties of doped glasses were studied by X-ray diffraction (XRD), scanning electric microscope (SEM), UV-VIS spectray analysis and Faraday rotation test etc.

Universal Biomolecule Binding Interlayers Created by Energetic Ion Bombardment

2011 ◽  
Vol 1354 ◽  
Author(s):  
Marcela M.M. Bilek ◽  
David R. McKenzie ◽  
Daniel V. Bax ◽  
Alexey Kondyurin ◽  
Yongbai Yin ◽  
...  
Keyword(s):  
Covalent Immobilization ◽  
Covalent Attachment ◽  
Structure And Properties ◽  
Early Disease ◽  
Flow Reactors ◽  
Early Disease Detection ◽  
Detailed Kinetic Model ◽  
Continuous Flow Reactors ◽  
New Applications ◽  
Chemical Textile

ABSTRACTThe ability to strongly attach biomolecules such as enzymes and antibodies to surfaces underpins a host of technologies that are rapidly growing in utility and importance. Such technologies include biosensors for medical and environmental applications and protein or antibody diagnostic arrays for early disease detection. Emerging new applications include continuous flow reactors for enzymatic chemical, textile or biofuels processing and implantable biomaterials that interact with their host via an interfacial layer of active biomolecules. In many of these applications it is desirable to maintain physical properties of an underlying material whilst engineering a surface suitable for attachment of proteins or peptide constructs. Nanoscale polymeric interlayers are attractive for this purpose.We have developed interlayers[1] that form the basis of a new biomolecule binding technology with significant advantages over other currently available methods. The interlayers, created by the ion implantation of polymer like surfaces, achieve covalent immobilization on immersion of the surface in protein solution. The interlayers can be created on any underlying material and ion stitched into its surface. The covalent immobilization of biomolecules from solution is achieved through the action of highly reactive free radicals in the interlayer.In this paper, we present characterisation of the structure and properties of the interlayers and describe a detailed kinetic model for the covalent attachment of protein molecules directly from solution.

scholarly journals Rational design of boron-dipyrromethene (BODIPY) reporter dyes for cucurbit[7]uril

2018 ◽  
Vol 14 ◽  
pp. 1961-1971 ◽  
Author(s):  
Mohammad A Alnajjar ◽  
Jürgen Bartelmeß ◽  
Robert Hein ◽  
Pichandi Ashokkumar ◽  
Mohamed Nilam ◽  
...  
Keyword(s):  
Rational Design ◽  
Photophysical Properties ◽  
Visible Spectral Region ◽  
Correlation Spectroscopy ◽  
Binding Motif ◽  
Binding Affinities ◽  
Binding Motifs ◽  
Host Guest Complex ◽  
Boron Dipyrromethene ◽  
New Applications

We introduce herein boron-dipyrromethene (BODIPY) dyes as a new class of fluorophores for the design of reporter dyes for supramolecular host–guest complex formation with cucurbit[7]uril (CB7). The BODIPYs contain a protonatable aniline nitrogen in the meso-position of the BODIPY chromophore, which was functionalized with known binding motifs for CB7. The unprotonated dyes show low fluorescence due to photoinduced electron transfer (PET), whereas the protonated dyes are highly fluorescent. Encapsulation of the binding motif inside CB7 positions the aniline nitrogen at the carbonyl rim of CB7, which affects the pK a value, and leads to a host-induced protonation and thus to a fluorescence increase. The possibility to tune binding affinities and pK a values is demonstrated and it is shown that, in combination with the beneficial photophysical properties of BODIPYs, several new applications of host–dye reporter pairs can be implemented. This includes indicator displacement assays with favourable absorption and emission wavelengths in the visible spectral region, fluorescence correlation spectroscopy, and noncovalent surface functionalization with fluorophores.

Introductory remarks

1983 ◽  
Vol 310 (1511) ◽  
pp. 5-5 ◽  
Keyword(s):  
Cement Hydration ◽  
Structure And Properties ◽  
Structure Property ◽  
Property Relations ◽  
Technological Advances ◽  
Fundamental Understanding ◽  
Potential Applications ◽  
Ready Availability ◽  
New Applications ◽  
Present Understanding

World manufacture of hydraulic cements is close to one thousand million tonnes per year, and cements along with steel are the most important constructional materials. Yet our understanding of the structure and properties of cements is not anything like as advanced as that of steels. But the cheapness and ready availability of the primary product, the facts that the energy consumed in manufacture is considerably smaller than that for metals, plastics, or ceramics and that hardening takes place with water at ordinary temperatures, provides the motivation for improving the strength, toughness and durability of cements not only for their more conventional uses, but also so that they might be used in quite new applications as replacements for energy intensive plastics, metals and ceramics. During the last 5—10 years there have been significant advances in fundamental understanding of the physics and chemistry of cements, and various recipes are available for cements with much improved properties. The aims of this meeting are to review the present understanding of structure-property relations, and cement hydration, to describe the improvements in properties that have been obtained so far, and to discuss the potential applications of such materials. The organizers hope that this meeting, which has attracted people from different disciplines, researchers, and industrial producers and users, will not only help to stimulate research aimed at further improvements, but even more important, also help to promote the very difficult process of the transfer of the technological advances.

A new 3D POMOF with two channels consisting of Wells–Dawson arsenotungstate and {Cl4Cu10(pz)11} complexes: synthesis, crystal structure, and properties

2018 ◽  
Vol 42 (6) ◽  
pp. 4596-4602 ◽  
Author(s):  
Bo-Wen Cong ◽  
Zhan-Hua Su ◽  
Zhi-Feng Zhao ◽  
Wen-Qi Zhao ◽  
Xiu-Juan Ma ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Photocatalytic Activity ◽  
Topological Structure ◽  
Hydrothermal Reaction ◽  
Structure And Properties ◽  
Photoluminescence Properties ◽  
Excellent Photocatalytic Activity

A new 3D POMOF based on Wells–Dawson arsenotungstate was prepared using a hydrothermal reaction. The POMOF exhibits a novel topological structure, photoluminescence properties, and excellent photocatalytic activity.

Effect of Bulky Functional Groups on Donor and Acceptor Interactions and their Photoluminescence Properties

ChemPhysChem ◽  
2020 ◽  
Vol 21 (22) ◽  
pp. 2620-2626
Author(s):  
Kai Lin Woon ◽  
Siti Aisyah Syaerah Mustapa ◽  
Nor Shafiq Mohd Jamel ◽  
Vannajan Sanghiran Lee ◽  
Muhammad Zhafran Zakaria ◽  
...  
Keyword(s):  
Functional Groups ◽  
Photoluminescence Properties ◽  
Donor And Acceptor

A STUDY ON THE PHOTOLUMINESCENCE PROPERTIES OF POROUS 6H-SiC(p) AND SiC FILM ON p-Si SUBSTRATE

2008 ◽  
Vol 22 (06) ◽  
pp. 415-424 ◽  
Author(s):  
K. BOURENANE ◽  
A. KEFFOUS ◽  
M. KECHOUANE ◽  
A. BOURENANE ◽  
G. NEZZAL ◽  
...  
Keyword(s):  
Electrochemical Etching ◽  
Broad Band ◽  
Structure And Properties ◽  
Photoluminescence Properties ◽  
Thin Metallic Film ◽  
Blue Band ◽  
Order Of Magnitude ◽  
P Type ◽  
Porous Sic ◽  
Sic Film

P-type porous SiC layers were fabricated by anodization of a hot-pressed p-type 6H-SiC (30 kΩcm) and a 1.6 μm SiC film was deposited onto p-type Si (100) substrate by Pulsed Laser Deposition (PLD) in HF. In order to facilitate the electrochemical etching of the substrate, ethylene glycol electrolyte has been added to the solution and a thin metallic film of aluminium ( Al ) has been deposited onto a SiC prior to anodization. The structure and properties of the porous SiC layer formed by this method were investigated by Scanning Electron Microscopy (SEM) and Photoluminescence (PL). It shows that photoluminescence spectra exhibit two emission bands centered at 2.20 eV (blue band) and an extended broad band from 2.20 to 3.22 eV (green band) from porous 6H-SiC (PSC). On the contrary, porous thin 1.6 μm SiC layer exhibits only a blue band centered at 2.95 eV. Finally, the results indicate clearly that porous SiC gives off green and blue light. Also, there is a shift to blue luminescence with the same order of magnitude when using a thin SiC layer deposited onto silicon (p- Si (100)).

Sign in / Sign up

Export Citation Format

Share Document