Notizen:Phosphorescence Decay in Thallium-Doped Ammonium Chloride

Abstract The phosphorescence decay rates of thallium-doped ammonium chloride (NH4Cl:Tl) phosphors, prepared by crystallization from aqueous solution, have been studied at room temperature for near-ultraviolet emission. The effects of impurity concentration as well as thermal and/or mechanical treatment on the decay rates have been examined. Phosphorescence centres consisting of a Tl+ion and a nearby negative ion vacancy are suggested to be responsible for the observed luminescence decay. The changes in the decay characteristics after pretreatments are explained on the basis of the location of the centres in normal and distorted regions of the host lattice.

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Hydrothermal synthesis of Co-doped In2S3 micropompons and their physical properties

Journal of Materials Research ◽

10.1557/jmr.2008.0113 ◽

2008 ◽

Vol 23 (4) ◽

pp. 917-923 ◽

Cited By ~ 9

Author(s):

Anuja Datta ◽

Dibyendu Ganguli ◽

Subhadra Chaudhuri

Keyword(s):

Room Temperature ◽

Lattice Structure ◽

Blue Shift ◽

Lattice Parameter ◽

Host Lattice ◽

Ultraviolet Emission ◽

Paramagnetic Resonance ◽

Optical Absorbance ◽

Resonance Band ◽

Co Doped

In2−xCoxS3 (x = 0 to 0.1) micropompons (diameters ∼3–4 μm) consisting of ∼10–15-nm-thick randomly self-assembled nanoflakes were synthesized hydrothermally. X-ray study indicated a steady variation of lattice parameter ratio up to 5% Co. Detailed investigations of the Co incorporation in In2S3 were carried out by optical absorbance, room temperature photoluminescence (PL), and electron paramagnetic resonance (EPR) studies. Significant blue shift in the absorbance spectra was noticed due to the crystal-field splitting of Co2+ ions in the host lattice structure. Unlike the visible emission found in undoped In2S3, PL spectra of the Co-doped samples were recognized by a strong ultraviolet emission peak at ∼335 nm, introduced by the t2g level of Co2+ ions, with maximum intensity for 5% Co. Room-temperature and low-temperature EPR spectra revealed octet paramagnetic bands up to 5% Co beyond which a single resonance band appeared.

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Growth of epitaxial ZnO thin film by oxidation of epitaxial ZnS thin films on Si(111)

International Journal of Modern Physics B ◽

10.1142/s0217979201008858 ◽

2001 ◽

Vol 15 (28n30) ◽

pp. 3861-3864

Author(s):

A. Miyake ◽

H. Kominami ◽

T. Aoki ◽

H. Tatsuoka ◽

H. Kuwabara ◽

...

Keyword(s):

Thin Film ◽

Room Temperature ◽

Epitaxial Films ◽

Driving Voltage ◽

Zno Thin Film ◽

Si Substrate ◽

Ultraviolet Emission ◽

Near Ultraviolet ◽

Novel Method ◽

First Time

The growth of epitaxial ZnO thin film on Si substrate by the oxidation of epitaxial ZnS film is a novel method and we are reporting this first time. The merits of the use of Si substrate are to make driving voltage in LED lower and less expensive than sapphire substrate. In this study, the epitaxial ZnO thin film could be successfully grown on the Si substrate. The epitaxial films showed a strong near ultraviolet emission peaked at around 3.32 eV at room temperature under 325 nm excitation.

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Room temperature near-ultraviolet emission from In-rich InGaN∕GaN multiple quantum wells

Applied Physics Letters ◽

10.1063/1.1923177 ◽

2005 ◽

Vol 86 (19) ◽

pp. 192105 ◽

Cited By ~ 27

Author(s):

Soon-Yong Kwon ◽

Sung-Il Baik ◽

Young-Woon Kim ◽

Hee Jin Kim ◽

Dong-Su Ko ◽

...

Keyword(s):

Quantum Wells ◽

Room Temperature ◽

Multiple Quantum Wells ◽

Multiple Quantum ◽

Ultraviolet Emission ◽

Near Ultraviolet

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Atmospheric Pressure Synthesis of ZnO Nanotubes by Aqueous Solution Route

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.669.189 ◽

2013 ◽

Vol 669 ◽

pp. 189-193

Author(s):

Jun Huang ◽

Xiao Jing Lv ◽

Mi Ouyang ◽

Bin Hu ◽

Cheng Zhang

Keyword(s):

Electron Microscopy ◽

Aqueous Solution ◽

Atmospheric Pressure ◽

Ultraviolet Emission ◽

Visible Absorption ◽

Selected Area Electron Diffraction ◽

Near Ultraviolet ◽

Transmission Electron ◽

Zno Nanotubes ◽

Solution Route

Single-crystalline ZnO nanotubes were fabricated via a simple aqueous solution method under low temperature and atmospheric pressure conditions. X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FE-SEM) and high-resolution transmission electron microscopy (HR-TEM) equipped with the selected area electron diffraction (SAED) setup were used to analyze the crystal structure, surface morphology and inner structure of ZnO nanotubes. Photoluminescence (PL) and UV-visible absorption spectra were carried out to investigate optical properties of ZnO nanotubes. The results indicate ZnO nanotubes only exhibit sharp and strong near ultraviolet emission at 363 nm according to PL spectrum.

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Strong Room-Temperature Near-Ultraviolet Emission from In-Rich InGaN/GaN Nanostructures Grown by Metalorganic Chemical Vapor Deposition

Japanese Journal of Applied Physics ◽

10.1143/jjap.44.7217 ◽

2005 ◽

Vol 44 (10) ◽

pp. 7217-7220 ◽

Cited By ~ 1

Author(s):

Soon-Yong Kwon ◽

Hee Jin Kim ◽

Young-Woon Kim ◽

Euijoon Yoon

Keyword(s):

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Room Temperature ◽

Metalorganic Chemical Vapor Deposition ◽

Chemical Vapor ◽

Ultraviolet Emission ◽

Near Ultraviolet ◽

Metalorganic Chemical

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Practical Synthesis of 2-Iodosobenzoic Acid (IBA) without Contamination by Hazardous 2-Iodoxybenzoic Acid (IBX) under Mild Conditions

Molecules ◽

10.3390/molecules26071897 ◽

2021 ◽

Vol 26 (7) ◽

pp. 1897

Author(s):

Hideyasu China ◽

Nami Kageyama ◽

Hotaka Yatabe ◽

Naoko Takenaga ◽

Toshifumi Dohi

Keyword(s):

Aqueous Solution ◽

Room Temperature ◽

Practical Method ◽

Hypervalent Iodine ◽

Mild Conditions ◽

Sequential Procedures ◽

Iodine Compounds ◽

Practical Synthesis ◽

Iodosobenzoic Acid ◽

Lower Temperature

We report a convenient and practical method for the preparation of nonexplosive cyclic hypervalent iodine(III) oxidants as efficient organocatalysts and reagents for various reactions using Oxone® in aqueous solution under mild conditions at room temperature. The thus obtained 2-iodosobenzoic acids (IBAs) could be used as precursors of other cyclic organoiodine(III) derivatives by the solvolytic derivatization of the hydroxy group under mild conditions of 80 °C or lower temperature. These sequential procedures are highly reliable to selectively afford cyclic hypervalent iodine compounds in excellent yields without contamination by hazardous pentavalent iodine(III) compound.

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Self-assembly induced luminescence of Eu3+-complexes and application in bioimaging

National Science Review ◽

10.1093/nsr/nwab016 ◽

2021 ◽

Author(s):

Ping-Ru Su ◽

Tao Wang ◽

Pan-Pan Zhou ◽

Xiao-Xi Yang ◽

Xiao-Xia Feng ◽

...

Keyword(s):

Aqueous Solution ◽

Rare Earth ◽

Luminescence Intensity ◽

Self Assembly ◽

Room Temperature ◽

Molecular Motion ◽

Proof Of Concept ◽

Room Temperature Phosphorescence ◽

New Strategy ◽

Size Controlled

Abstract Design and engineering of highly efficient emitting materials with assembly-induced luminescence, such as room temperature phosphorescence (RTP) and aggregation-induced emission (AIE), have stimulated extensive efforts. Here, we propose a new strategy to obtain size-controlled Eu3+-complex nanoparticles (Eu-NPs) with self-assembly induced luminescence (SAIL) characteristics without encapsulation or hybridization. Compared with previous RTP or AIE materials, the SAIL phenomena of increased luminescence intensity and lifetime in aqueous solution for the proposed Eu-NPs are due to the combined effect of self-assembly in confining the molecular motion and shielding the water quenching. As a proof of concept, we also show that this system can be further applied in bioimaging, temperature measurement and HClO sensing. The SAIL activity of the rare-earth (RE) system proposed here offers a further step forward on the roadmap for the development of RE light conversion systems and their integration in bioimaging and therapy applications.

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