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Chemical luminescence

Wenjin Yang, Baodan Liu, Tao Fang, Weimmerskirch-Aubatin Jennifer, Labbé Christophe, Zhaosheng Li, Xinglai Zhang, Xin Jiang
Two-dimensional semiconductors with layer thicknesses of a few nanometers to tens of nanometers have attracted tremendous research interest due to their fascinating electrical, optical, and optoelectronic properties and technologically important applications. In this work, two dimensional ternary ZnIn2S4 nanosheets which self-assemble into microflowers have been synthesized through a feasible chemical vapour deposition process. High-resolution transmission electron microscope (HRTEM) analysis reveals that the ZnIn2S4 nanostructure exhibits an extremely high phase purity and a single crystal nature free of dislocations, stacking faults or twins...
October 18, 2016: Nanoscale
Timothy A Johnson, Elisa A Rehak, Sushant P Sahu, David A Ladner, Ezra L Cates
Germicidal UVC radiation is a highly effective, chemical-free tool for bacteria inactivation, but its application is limited to reactors and open areas that can accommodate lamps/LEDs and wiring. A relevant example of problematic bacterial colonization within UV-inaccessible confines where chemical techniques have found only limited success is biofouling of feed channels in high-pressure membrane elements for water treatment. Herein we demonstrate a unique method of generating UV internally using embedded radioluminescent (RL) particles excited by an external X-ray source...
October 14, 2016: Environmental Science & Technology
Nathan D Rudd, Hao Wang, Erika M A Fuentes-Fernandez, Simon J Teat, Feng Chen, Gene Stephen Hall, Yves J Chabal, Jing Li
We have designed and synthesized an isoreticular series of luminescent metal-organic frameworks (LMOFs) by incorporating a strongly emissive molecular fluorophore and functionally diverse co-linkers into Zn-based structures. The three-dimensional porous networks of LMOF-261, -262 and -263 represent a unique/new type of nets, classified as a 2-nodal, (4,4)-c net (mot-e type) with four-fold, class IIIa interpenetration. All compounds crystallize in body-centered tetragonal crystal system (space group I41/a). A systematic study has been implemented to analyze their interactions with heavy metals...
October 13, 2016: ACS Applied Materials & Interfaces
Hongjian Li, Panpan Li, Junjie Kang, Jiianfeng Ding, Jun Ma, Yiyun Zhang, Xiaoyan Yi, Guohong Wang
We have presented broadband full-color monolithic InGaN light-emitting diodes (LEDs) by self-assembled InGaN quantum dots (QDs) using metal organic chemical vapor deposition (MOCVD). The electroluminescence spectra of the InGaN QDs LEDs are extremely broad span from 410 nm to 720 nm with a line-width of 164 nm, covering entire visible wavelength range. A color temperature of 3370 K and a color rendering index of 69.3 have been achieved. Temperature-dependent photoluminescence measurements reveal a strong carriers localization effect of the InGaN QDs layer by obvious blue-shift of emission peak from 50 K to 300 K...
October 13, 2016: Scientific Reports
Bhushan P Kore, Shilpa A Pardhi, N S Dhoble, S J Dhoble, H C Swart
A series of single-phase phosphors based on Na6 Mg(SO4 )4 (Zeff  = 11.70) doped with Dy and Eu was prepared by the wet chemical method. The photoluminescence (PL) and thermoluminescence (TL) properties of Dy(3)(+) - and Eu(3)(+) -activated Na6 Mg(SO4 )4 phosphors were investigated. The characteristic emissions of Dy(3)(+) and Eu(3)(+) were observed in the Na6 Mg(SO4 )4 host. The TL glow curve of the Na6 Mg(SO4 )4 :Dy phosphor consisted of a prominent peak at 234°C and a very small hump at 158°C. The TL sensitivity of the Na6 Mg(SO4 )4 :Dy phosphor was found to be four times less than the commercialized CaSO4 :Dy phosphor...
October 10, 2016: Luminescence: the Journal of Biological and Chemical Luminescence
Quan Xu, Yao Liu, Rigu Su, Lulu Cai, Bofan Li, Yingyuan Zhang, Linzhou Zhang, Yajun Wang, Yan Wang, Neng Li, Xiao Gong, Zhipeng Gu, Yusheng Chen, Yanglan Tan, Chenbo Dong, Theruvakkattil Sreenivasan Sreeprasad
Heteroatom doped carbon dots (CDs), with high photoluminescence quantum yield (PLQY), are of keen interest in various applications such as chemical sensors, bio-imaging, electronics, and photovoltaics. Zinc, an important element assisting the electron-transfer process and an essential trace element for cells, is a promising metal dopant for CDs, which could potentially lead to multifunctional CDs. In this contribution, we report a single-step, high efficiency, hydrothermal method to synthesize Zn-doped carbon dots (Zn-CDs) with a superior PLQY...
October 11, 2016: Nanoscale
Chih-Min Wang, Li-Wei Lee, Tsung-Yuan Chang, Bing-Lun Fan, Chih-Ling Wang, Hsiu-Mei Lin, Kuang-Lieh Lu
A new 3D tubular zinc phosphite, Zn2 (C22 H22 N8 )0.5 (HPO3 )2 ⋅H2 O (1), incorporating a tetradentate organic ligand was synthesized under hydro(solvo)thermal conditions and structurally characterized by single-crystal X-ray diffraction. Compound 1 is the first example of inorganic zincophosphite chains being interlinked through 1,2,4,5-tetrakis(imidazol-1-ylmethyl)benzene to form a tubular porous framework with unusual organic-inorganic hybrid channels. The thermal and chemical stabilities, high capacity for CO2 adsorption compared to that for N2 adsorption, and interesting optical properties of LED devices fabricated using this compound were also studied...
November 2, 2016: Chemistry: a European Journal
Helen M Burke, Thorfinnur Gunnlaugsson, Eoin M Scanlan
The development of synthetic chemical probes for the detection of enzymes is extremely important for biological, medicinal, and industrial applications. Here we report the synthesis of an array of novel glycosylated Tb(iii) complexes, their photophysical properties in solution, and their ability to function as luminescent probes for observing glycosidase enzyme activity in real time. Our initial studies into the application of these complexes for the detection of the Concanavalin A (ConA) lectin is also reported, highlighting the broad scope of these novel chemical probes...
September 26, 2016: Organic & Biomolecular Chemistry
Francesca Scarpelli, Andreea Ionescu, Loredana Ricciardi, Pierluigi Plastina, Iolinda Aiello, Massimo La Deda, Alessandra Crispini, Mauro Ghedini, Nicolas Godbert
The synthesis and photophysical characterization of a new family of luminescent water-soluble ionic iridium(iii) complexes of the general formula [(ppy)2Ir(bpy)]X are reported. The Ir(iii) complexes incorporate a cyclometalated 2-phenylpyridine (ppy), the ancillary ligand 2,2'-bipyridyl (bpy) and different counterions (X(-) = EtO(-), OH(-), EtOCH2CO2(-), MeOCH2CO2(-)). These complexes were obtained starting from the cyclometalated Ir(iii) chloro-bridged dimer [(ppy)2Ir(μ-Cl)]2, for the first time synthesized through a new microwave assisted synthetic procedure, and subsequently converted into the corresponding hydroxy-bridged dimer [(ppy)2Ir(μ-OH)]2...
October 7, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
Zhixiang Lu, Mingjiang Wu, Shuang Wu, Shaoxiong Yang, Yuan Li, Xiaolan Liu, Liyan Zheng, Qiue Cao, Zhongtao Ding
Transformation of aggregation induced emission (AIE) molecules into functional materials can greatly tune their fluorescence properties and expand their related potential applications. Here, we demonstrate a facile strategy to modulate the fluorescence properties of AIE molecules by confining them within the nanochannels of metal-organic frameworks (MOFs). AIE molecules (4,4'-(hydrazine-1,2-diylidene bis(methanylylidene)) bis(3-hydroxybenzoic acid), HDBB) with pH-dependent emission were successfully integrated into UiO-66 resulting in a UiO-66⊃HDBB complex while maintaining the crystal structure by the host-guest process...
October 14, 2016: Nanoscale
M El Sayed Moussa, S Evariste, H-L Wong, L Le Bras, C Roiland, L Le Polles, B Le Guennic, K Costuas, V W-W Yam, C Lescop
The straightforward synthesis of a new Cu(i) metal-rich small metallacycle is presented. This compound is luminescent in the solid state with an emission quantum yield of 72% at room temperature and displays a pronounced reversible red-shift of its emission spectra upon cooling. Quantum chemical calculations reveal that these properties are governed by important geometrical relaxations that imply the formation of cuprophilic interactions at the excited states.
September 15, 2016: Chemical Communications: Chem Comm
Yilong Lei, Yanqiu Sun, Hongyang Zhang, Liangsheng Liao, Shuit-Tong Lee, Wai-Yeung Wong
We develop a novel and facile chemical reaction route to modulate the crystallization process of luminescent zinc 8-hydroxyquinoline (Znq2) particles. Polyvinylpyrrolidone (PVP)-modified octahedral Znq2 micro- and nano-crystals were used as seeds to construct two distinct hybrid structures, i.e., Znq2@ZIF-8 core-shell and multiple Znq2 particles on each ZIF-8.
October 11, 2016: Chemical Communications: Chem Comm
Ondřej Cibulka, Christoph Vorkötter, Adam Purkrt, Jakub Holovský, Jan Benedikt, Kateřina Herynková
This work compares structural and optical properties of silicon nanocrystals prepared by two fundamentally different methods, namely, electrochemical etching of Si wafers and low-pressure plasma synthesis, completed with a mechano-photo-chemical treatment. This treatment leads to surface passivation of the nanoparticles by methyl groups. Plasma synthesis unlike electrochemical etching allows selecting of the particle sizes. Measured sizes of the nanoparticles by dynamic light scattering show 3 and 20 nm for electrochemically etched and plasma-synthetized samples, respectively...
December 2016: Nanoscale Research Letters
Sanyang Han, Xian Qin, Zhongfu An, Yihan Zhu, Liangliang Liang, Yu Han, Wei Huang, Xiaogang Liu
Meeting the high demand for lanthanide-doped luminescent nanocrystals across a broad range of fields hinges upon the development of a robust synthetic protocol that provides rapid, just-in-time nanocrystal preparation. However, to date, almost all lanthanide-doped luminescent nanomaterials have relied on direct synthesis requiring stringent controls over crystal nucleation and growth at elevated temperatures. Here we demonstrate the use of a cation exchange strategy for expeditiously accessing large classes of such nanocrystals...
October 4, 2016: Nature Communications
S Brodbeck, H Suchomel, M Amthor, T Steinl, M Kamp, C Schneider, S Höfling
We show that, by monitoring the free carrier reservoir in a GaAs-based quantum well microcavity under nonresonant pulsed optical pumping, lasing supported by a fermionic reservoir (photon lasing) can be distinguished from lasing supported by a reservoir of bosons (polariton lasing). Carrier densities are probed by measuring the photocurrent between lateral contacts deposited directly on the quantum wells of a microcavity that are partially exposed by wet chemical etching. We identify two clear thresholds in the input-output characteristic of the photoluminescence signal which can be attributed to polariton and photon lasing, respectively...
September 16, 2016: Physical Review Letters
Lorenzo Sansalone, Sicheng Tang, Yang Zhang, Ek Raj Thapaliya, Françisco M Raymo, Jaume Garcia-Amorós
Photochromic or photocaged ligands can be anchored to the outer shell of semiconductor quantum dots in order to control the photophysical properties of these inorganic nanocrystals with optical stimulations. One of the two interconvertible states of the photoresponsive ligands can be designed to accept either an electron or energy from the excited quantum dots and quench their luminescence. Under these conditions, the reversible transformations of photochromic ligands or the irreversible cleavage of photocaged counterparts translates into the possibility to switch luminescence with external control...
October 2016: Top Curr Chem (J)
Yasuhisa Inada, Akira Hashiya, Mitsuru Nitta, Shogo Tomita, Akira Tsujimoto, Masa-Aki Suzuki, Takeyuki Yamaki, Taku Hirasawa
Controlling the characteristics of photon emission represents a significant challenge for both fundamental science and device technologies. Research on microcavities, photonic crystals, and plasmonic nanocavities has focused on controlling spontaneous emission by way of designing a resonant structure around the emitter to modify the local density of photonic states. In this work, we demonstrate resonantly enhanced emission using luminescent nanostructured waveguide resonance (LUNAR). Our concept is based on coupling between emitters in the luminescent waveguide and a resonant waveguide mode that interacts with a periodic nanostructure and hence outcouples via diffraction...
September 29, 2016: Scientific Reports
Mousumi Chatterjee, Bhavya Srivastava, Milan K Barman, Bhabatosh Mandal
A time-cost effective, chemically stable mesoporous resin (FSG-PAN), simultaneous binder of two different metal centers (both high (Cd(II)) and low (Tl(I)) oxidation states), has been synthesized by immobilizing azo-dye (1-(2-pyridylazo)-2-napthol: PAN) on functionalized silica gel (FSG). Its corresponding synthesized nano material possesses good luminescent properties, and has been utilized in fluoride sensing at trace levels (1.8 × 10(-6) - 7.2 × 10(-6) M). The composition ({Si[OSi]p=4[H2O]x=0.81}12[-Si(CH3)2-NH-C6H4-N=N-PAN]4...
2016: Analytical Sciences: the International Journal of the Japan Society for Analytical Chemistry
Hang Xu, Bin Zhai, Chun-Shuai Cao, Bin Zhao
A novel three-dimensional lanthanide-organic framework {[Eu(BTB)(phen)]·4.5DMF·2H2O}n (1) has been synthesized. Structural characterization suggests that framework 1 possesses one-dimensional channels with potential pore volume, and the large channels in the framework can capture CO2. Interestingly, investigations on the cycloaddition reaction of CO2 and epoxides reveal that compound 1 can be considered as an efficient catalyst for CO2 fixation with epoxides under 1 atm pressure. Importantly, 1 can be reused at least five times without any obvious loss in catalytic activity...
October 3, 2016: Inorganic Chemistry
Xiyu Li, Haifeng Chen
The exploration of bone reconstruction with time requires the combination of a biological method and a chemical technique. Lanthanide Yb(3+) and Ho(3+) co-doped fluorapatite (FA:Yb(3+)/Ho(3+)) and hydroxyapatite (HA:Yb(3+)/Ho(3+)) particles with varying dopant concentrations were prepared by hydrothermal synthesis and thermal activation. Controllable green and red upconversion emissions were generated under 980 nm near-infrared excitation; the FA:Yb(3+)/Ho(3+) particles resulted in superior green luminescence, while HA:Yb(3+)/Ho(3+) dominated in red emission...
October 7, 2016: ACS Applied Materials & Interfaces
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