Pressure‐Treated Engineering to Harvest Enhanced Green Emission in Mn‐Based Organic–Inorganic Metal Halides at Ambient Conditions

Abstract Single crystals of pure (PPB) and methyl orange dye doped Potassium Penta Borate octa hydrate (MOPPB) are grown by slow evaporation technique at ambient conditions. Single crystal X-Ray Diffraction study verifies the orthorhombic family of both pure and MO doped PPB crystals. FTIR assures the incorporation of MO dye into PPB crystals. The Reverse Indentation Size Effect (RISE) behavior and soft nature of both pure and MO doped PPB crystals are verified by the Micro Hardness Study. Absorbance studies shows PPB possess lower cut-off wavelength at 190 nm due to π-π* transitions whereas MOPPB crystals have two peaks, one at 278.60 nm due to π-π* transitions and the second one at 464.65 nm due to n-π* transitions. The inclusion of MO dye molecules alters the band structure resulting in reduction of bandgap to 5.7 eV (MOPPB) from 5.91 eV (PPB). Kurtz powder test shows green emission in both pure PPB and MOPPB with relative SHG efficiency of 0.45 times and 0.40 times that of SHG output of KDP. Z-scan studies performed with 785 nm laser excitation exposes that both pristine and MO doped PPB crystal exhibit reverse saturable nonlinear absorption and self-focusing nonlinear refraction which is thermo-optic in origin. Two photon absorption induced optical limiting action is demonstrated in both PPB and MOPPB crystals. Increase in NLO coefficient due to MO dye confirms the superiority of MOPPB than PPB for optical limiting applications.

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Growth and Characterization of Ce3+doped Calciumferrate(III) Type Crystals

Acta Crystallographica Section A Foundations and Advances ◽

10.1107/s2053273314088901 ◽

2014 ◽

Vol 70 (a1) ◽

pp. C1109-C1109

Author(s):

Detlef Klimm ◽

Jan Philippen ◽

Christo Guguschev

Keyword(s):

Crystal Growth ◽

Single Crystal ◽

Broad Band ◽

Green Emission ◽

Charge Compensation ◽

Ligand Field ◽

Ambient Conditions ◽

Low Oxygen ◽

Tem Analysis ◽

Alkaline Oxides

Ce3+ ions in oxide hosts show broad optical emission in the green spectral range, because of a strong ligand field. Substances such as Ce3+ doped CaSc2O4 and SrY2O4 crystallizing in the calciumferrate(III) structure type are used as ceramic phosphors for white LED's. However, under ambient conditions cerium prefers the 4-valent state, e.g. CeO2. For the ceramics, charge compensation and incorporation of Ce3+ can be reached by adding alkaline oxides, where e.g. (Na+, Ce3+) are substituting (2 Ca2+). Unfortunately, this option is not feasible for single crystal growth from the melt, because at the very high melting points near 21000C (CaSc2O4, [1]) or even 22000C (SrY2O4, [2]) alkaline oxides are evaporating completely. It will be shown that nevertheless efficient Ce3+ doping of both hosts can be obtained if melt crystal growth is performed in a suitable atmosphere with sufficiently low oxygen fugacity. First crystal growth experiments where performed by LHPG (Laser Heated Pedestal Growth), but meanwhile bulk growth by the Czochralski technique is feasible too. The figure shows such Ce3+:CaSc2O4 single crystal. Especially Ce3+:CaSc2O4 shows efficient broad band green emission, and no foreign phases indicating Ce4+ (CeO2) can be detected by X-ray diffraction. TEM analysis hints on incorporation of Ce3+ on a Ca2+ site.

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Unraveling the Near-Unity Narrow-Band Green Emission in Zero-Dimensional Mn2+-Based Metal Halides: A Case Study of (C10H16N)2Zn1–xMnxBr4 Solid Solutions

The Journal of Physical Chemistry Letters ◽

10.1021/acs.jpclett.0c01933 ◽

2020 ◽

Vol 11 (15) ◽

pp. 5956-5962 ◽

Cited By ~ 3

Author(s):

Guojun Zhou ◽

Zhiyang Liu ◽

Jinglong Huang ◽

Maxim S. Molokeev ◽

Zewen Xiao ◽

...

Keyword(s):

Solid Solutions ◽

Narrow Band ◽

Green Emission ◽

Metal Halides

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Hydrogen bonding in liquid methanol at ambient conditions and at high pressure

Molecular Physics ◽

10.1080/002689700162694 ◽

2000 ◽

Vol 98 (3) ◽

pp. 125-134 ◽

Cited By ~ 10

Author(s):

T. Weitkamp, J. Neuefeind, H. E. Fisch

Keyword(s):

High Pressure ◽

Hydrogen Bonding ◽

Ambient Conditions

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Multifunction Scanning Probe Microscope with Diamond Tip. Nanotechnological Research at Ambient Conditions

Nauka ta innovacii ◽

10.15407/scin8.02.008 ◽

2012 ◽

Vol 8 (2) ◽

pp. 8-12

Author(s):

O.G. Lysenko ◽

Keyword(s):

Scanning Probe Microscope ◽

Scanning Probe ◽

Ambient Conditions ◽

Probe Microscope

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Growth Kinetics of Quantum Size ZnO Particles

MRS Proceedings ◽

10.1557/proc-536-347 ◽

1998 ◽

Vol 536 ◽

Author(s):

E. M. Wong ◽

J. E. Bonevich ◽

P. C. Searson

Keyword(s):

Growth Kinetics ◽

Ostwald Ripening ◽

Chemical Potential ◽

Colloidal Suspensions ◽

Green Emission ◽

Blue Shift ◽

Constant Current ◽

Mass Model ◽

Zno Particles ◽

Kinetics Of

AbstractColloidal chemistry techniques were used to synthesize ZnO particles in the nanometer size regime. The particle aging kinetics were determined by monitoring the optical band edge absorption and using the effective mass model to approximate the particle size as a function of time. We show that the growth kinetics of the ZnO particles follow the Lifshitz, Slyozov, Wagner theory for Ostwald ripening. In this model, the higher curvature and hence chemical potential of smaller particles provides a driving force for dissolution. The larger particles continue to grow by diffusion limited transport of species dissolved in solution. Thin films were fabricated by constant current electrophoretic deposition (EPD) of the ZnO quantum particles from these colloidal suspensions. All the films exhibited a blue shift relative to the characteristic green emission associated with bulk ZnO. The optical characteristics of the particles in the colloidal suspensions were found to translate to the films.

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Hybrid Micro-Optical Sensors via Sol-Gel Soft Lithography

MRS Proceedings ◽

10.1557/proc-628-cc9.3 ◽

2000 ◽

Vol 628 ◽

Cited By ~ 1

Author(s):

Mark A. Clarner ◽

Michael J. Lochhead

Keyword(s):

Optical Sensors ◽

Soft Lithography ◽

Sol Gel ◽

Silica Gels ◽

Ph Sensing ◽

Ambient Conditions ◽

Sensor Applications ◽

Patterned Structures ◽

Biological Functionality ◽

Indicator Dyes

ABSTRACTOrganically modified silica gels and dye-doped silica gels have been patterned into micrometer-scale structures on a substrate using micro molding in capillaries (MIMIC). This approach is from a class of elastomeric stamping and molding techniques collectively known as soft lithography. Soft lithography and sol-gel processing share attractive features in that they are relatively benign processes performed at ambient conditions, which makes both techniques compatible with a wide variety of organic molecules, molecular assemblies, and biomolecules. The combination of sol-gel and soft lithography, therefore, holds enormous promise as a tool for microfabrication of materials with optical, chemical, or biological functionality that are not readily patterned with conventional methods. This paper describes our investigation of micro-patterned organic-inorganic hybrid materials containing indicator dyes for microfluidic sensor applications. Reversible colorimetric pH sensing via entrapped reagents is demonstrated in a prototype microfluidic sensor element. Patterned structures range from one to tens of micrometers in cross-section and are up to centimeters in length. Fundamental chemical processing issues associated with mold filling, cracking and sensor stability are discussed.

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Fluorescence of BODIPY Dyes in Gas Phase at near Ambient Conditions

10.26434/chemrxiv.11639931.v1 ◽

2020 ◽

Author(s):

Kseniya A. Mariewskaya ◽

Denis Larkin ◽

Yuri Samoilichenko ◽

Vladimir Korshun ◽

Alex Ustinov

Keyword(s):

Gas Phase ◽

Molecular Interactions ◽

Atmospheric Pressure ◽

Fluorescence Spectra ◽

Visible Range ◽

Intrinsic Properties ◽

Ambient Conditions ◽

Ideal Model ◽

Molecular Fluorescence ◽

Tesla Coil

Molecular fluorescence is a phenomenon that is usually observed in condensed phase. It is strongly affected by molecular interactions. The study of fluorescence spectra in the gas phase can provide a nearly-ideal model for the evaluation of intrinsic properties of the fluorophores. Unfortunately, most conventional fluorophores are not volatile enough to allow study of their fluorescence in the gas phase. Here we report very bright gas phase fluorescence of simple BODIPY dyes that can be readily observed at atmospheric pressure using conventional fluorescence instrumentation. To our knowledge, this is the first example of visible range gas phase fluorescence at near ambient conditions. Evaporation of the dye in vacuum allowed us to demonstrate organic molecular electroluminescence in gas discharge excited by electric field produced by a Tesla coil.

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Yttrium Oxyhydrides for Photochromic Applications: Correlating Composition and Optical Response

10.26434/chemrxiv.7034585 ◽

2018 ◽

Author(s):

Dmitrii Moldarev ◽

Elbruz M. Baba ◽

Marcos V. Moro ◽

Chang C. You ◽

Smagul Zh. Karazhanov ◽

...

Keyword(s):

Medical Devices ◽

Ternary Diagram ◽

Optical And Electrical Properties ◽

Ambient Conditions ◽

Elastic Recoil ◽

Elastic Recoil Detection Analysis ◽

Photochromic Properties ◽

Smart Windows ◽

Elastic Recoil Detection ◽

Detection Analysis

It has been recently demonstrated that yttrium oxyhydride(YHO) films can exhibit reversible photochromic properties when exposed to illumination at ambient conditions. This switchable optical propertyenables their utilization in many technological applications, such as smart windows, sensors, goggles, medical devices, etc. However, how the composition of the films affects their optical properties is not fully clear and therefore demands a straightforward investigation. In this work, the composition of YHO films manufactured by reactive magnetron sputtering under different conditions is deduced in a ternary diagram from Time-of-Flight Elastic Recoil Detection Analysis (ToF-ERDA). The results suggest that stable compounds are formed with a specificchemical formula – YH2-δOδ. In addition, optical and electrical properties of the films are investigated, and a correlation with their compositions is established. The corresponding photochromic response is found in a specific oxygen concentration range (0.45 < δ < 1.5) with maximum and minimum of magnitude on the lower and higher border, respectively.

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Bringing Biocatalysis into the Deuteration Toolbox

10.26434/chemrxiv.7982864 ◽

2019 ◽

Cited By ~ 1

Author(s):

Jack Rowbotham ◽

Oliver Lenz ◽

Holly Reeve ◽

Kylie Vincent

Keyword(s):

Late Stage ◽

Hydrogen Isotope ◽

Reductive Amination ◽

Mechanistic Studies ◽

Ambient Conditions ◽

Synthetic Pathway ◽

Drug Candidates ◽

Isotopic Selectivity ◽

Reducing Equivalents

Chemicals labelled with the heavy hydrogen isotope deuterium (2H) have long been used in chemical and biochemical mechanistic studies, spectroscopy, and as analytical tracers. More recently, demonstration of selectively deuterated drug candidates that exhibit advantageous pharmacological traits has spurred innovations in metal-catalysed 2H insertion at targeted sites, but asymmetric deuteration remains a key challenge. Here we demonstrate an easy-to-implement biocatalytic deuteration strategy, achieving high chemo-, enantio- and isotopic selectivity, requiring only 2H2O (D2O) and unlabelled dihydrogen under ambient conditions. The vast library of enzymes established for NADH-dependent C=O, C=C, and C=N bond reductions have yet to appear in the toolbox of commonly employed 2H-labelling techniques due to requirements for suitable deuterated reducing equivalents. By facilitating transfer of deuterium atoms from 2H2O solvent to NAD+, with H2 gas as a clean reductant, we open up biocatalysis for asymmetric reductive deuteration as part of a synthetic pathway or in late stage functionalisation. We demonstrate enantioselective deuteration via ketone and alkene reductions and reductive amination, as well as exquisite chemo-control for deuteration of compounds with multiple unsaturated sites.

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