A Novel Phosphors of Cu+ Doped PbBrOH: Prepare, Luminescent Mechanism and Outstanding Properties

Titanium dioxide TiO2 nanorods were successfully grown on conductive glass FTO substrate using the hydrothermal method at a temperature of 160 oC. Surface topography, structure, and optical characteristics were studied according to the influence of annealing temperature (450, 550, and 650) oC. The surface topography results reveal that the TiO2 had nanorods structure with a tetragonal shape, and the rod diameter increases from 84.2 nm to 116.6 nm with increasing the annealing temperature. The crystal structure of the grown TiO2 NRs exhibits a high crystallinity of polycrystalline nature with anatase and rutile phases. The preferential orientation was along (204) plane for anatase tetragonal structure. AFM image shows an intense edge, uniform surface morphology, and increased grain diameter with annealing temperature. The optical properties of TiO2 NRs were investigated, and the absorption edge shows a blue shifting as the annealing temperature increases when considering the crystallinity and morphology changes. The energy band gap was found to be lower than 3 eV, which can be attributed to the presence of anatase and rutile phases with an increment range from 2.72 to 2.86 nm alongside the increase in the annealing temperature. The results indicate that the adopted hydrothermal method and the synthesized TiO2 NRs were suitable for photovoltaic and photocatalytic applications.

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Metavivianite, Fe2+Fe3+2(PO4)2(OH)2·6H2O: new data and formula revision

Mineralogical Magazine ◽

10.1180/minmag.2012.076.3.20 ◽

2012 ◽

Vol 76 (3) ◽

pp. 725-741 ◽

Cited By ~ 11

Author(s):

N. V. Chukanov ◽

R. Scholz ◽

S. M. Aksenov ◽

R. K. Rastsvetaeva ◽

I. V. Pekov ◽

...

Keyword(s):

Crystal Structure ◽

Gas Chromatography ◽

Optical Properties ◽

Crystal Chemical ◽

Chemical Formula ◽

Crystal Chemical Formula ◽

Homogeneous Sample ◽

X Ray ◽

Composition Structure ◽

First Time

AbstractThe composition, structure, X-ray powder diffraction pattern, optical properties, density, infrared, Raman and Mössbauer spectra, and thermal properties of a homogeneous sample of metavivianite from the Boa Vista pegmatite, near Galiléia, Minas Gerais, Brazil are reported for the first time. Metavivianite is biaxial (+) with α = 1.600(3), β = 1.640(3), γ = 1.685(3) and 2Vmeas= 85(5)°. The measured and calculated densities are Dmeas= 2.56(2) and Dcalc= 2.579 g cm–3. The chemical composition, based on electronmicroprobe analyses, Mössbauer spectroscopy (to determine the Fe2+:Fe3+ratio) and gas chromatography (to determine H2O) is MgO 0.70, MnO 0.92, FeO 17.98, Fe2O326.60, P2O528.62, H2O 26.5; total 101.32 wt.%. The empirical formula is (Fe3+1.64Fe2+1.23Mg0.085Mn0.06)Σ3.015(PO4)1.98(OH)1.72·6.36H2O. Metavivianite is triclinic, P1̄, a = 7.989(1), b = 9.321(2), c = 4.629(1) Å, α = 97.34(1), β = 95.96(1), γ = 108.59(2)°, V = 320.18(11) Å3and Z = 1. The crystal structure was solved using a single-crystal techniques to an agreement index R = 6.0%. The dominant cations in the independent sites are Fe2+and Fe3+, with multiplicities of 1 and 2, respectively. The simplified crystal-chemical formula for metavivianite is Fe2+(Fe3+, Fe2+)2(PO4)2(OH,H2O)2·6H2O; the endmember formula is Fe2+Fe3+2(PO4)2(OH)2·6H2O, which is dimorphous with ferrostrunzite.

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MmHn(XO4)(m + n)/2crystals: structure, phase transitions, hydrogen bonds, conductivity. II. Structure and properties of Cs3(HSO4)2(H2PO4) and Cs4(HSO4)3(H2PO4) single crystals

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520615023069 ◽

2016 ◽

Vol 72 (1) ◽

pp. 133-141 ◽

Cited By ~ 7

Author(s):

Irina Makarova ◽

Vadim Grebenev ◽

Elena Dmitricheva ◽

Ilya Vasiliev ◽

Vladimir Komornikov ◽

...

Keyword(s):

Crystal Structure ◽

Phase Diagram ◽

Optical Properties ◽

Phase Transitions ◽

Single Crystals ◽

Structural Features ◽

Structure And Properties ◽

Structure Phase ◽

Dielectric And Optical Properties ◽

First Time

Cs3(HSO4)2(H2PO4) and Cs4(HSO4)3(H2PO4) single crystals were obtained for the first time based on a systematic study of the phase diagram of the CsHSO4–CsH2PO4–H2O ternary system. To reveal the structural conditionality for anomalies in physical properties, including dielectric and optical properties, diffraction studies of the crystal structure of Cs3(HSO4)2(H2PO4) and Cs4(HSO4)3(H2PO4) were performed, and their common structural features and differences were analyzed.

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Structure and Optical Properties of Ca Silicide Films and Si/Ca3Si4/Si(111) Heterostructures

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.213.71 ◽

2014 ◽

Vol 213 ◽

pp. 71-79 ◽

Cited By ~ 2

Author(s):

Nikolay Gennadievich Galkin ◽

Dmitrii Aleksandrovich Bezbabnyi ◽

Sergei Andreevich Dotsenko ◽

Konstantin Nikolaevich Galkin ◽

Igor Mikhailovich Chernev ◽

...

Keyword(s):

Crystal Structure ◽

Thin Films ◽

Optical Properties ◽

Interband Transition ◽

Ex Situ ◽

Silicide Film ◽

First Time ◽

Phonon Structure

Thick, thin films and island of Ca silicide have been grown by Ca deposition onto 500 °C Si (111)7x7 substrates. The crystal structure of the grown layers strongly differs from the known Ca silicides (Ca2Si, CaSi, Ca5Si3, Ca14Si19, CaSi2). The phonon peaks at 389 and 416 cm-1 and the interband transition peaks (0.9-1.0, 1.3-1.7 and 2.0-2.5 eV) belongs to another silicide - Ca3Si4. Peculiarities of crystal, electronic, and phonon structure and optical properties of the grown Ca silicide films were measured by in situ and ex situ methods permit to state that the formed Ca silicide film has a composition Ca3Si4. Heterostructures with embedded Ca3Si4 films with different thicknesses have been formed atop the Ca3Si4 films by MBE and SPE at 500 °C. The observed density of pinholes with different sizes suggests the Si growth atop the Ca silicide follows a 3D mechanism. Photoluminescence was found first time in Si/Ca3Si4/Si (111) heterostructures.

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Improved Photocatalytic H2 Evolution from Inorganic/Organic Sacrificial Solution over Ni-Doped (CuIn)0.2Zn1.6S2 Photocatalysts

MRS Proceedings ◽

10.1557/opl.2011.1042 ◽

2011 ◽

Vol 1326 ◽

Author(s):

Xianghui Zhang ◽

Dengwei Jing ◽

Liejin Guo

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Hydrothermal Method ◽

H2 Evolution ◽

Doping Amount ◽

Ni Doping ◽

Sem Images ◽

Xrd Pattern ◽

Environmental Friendly ◽

Photocatalytic H2 Evolution

ABSTRACTThe Ni-doped (CuIn)0.2Zn1.6S2 photocatalysts were prepared via a two-step ultrasonic-hydrothermal method under an environmental-friendly condition. XRD pattern profiles suggested that Ni2+ successfully doped into (CuIn)0.2Zn1.6S2 lattice. UV-Vis spectra indicated that the optical properties of the photocatalysts greatly depended on the amount of Ni doped. SEM images show that the samples were microspheres. The microsphere structures were gradually damaged with the increment of Ni doping amount. The photoactivity of (CuIn)0.2Zn1.6S2 was enhanced when Ni2+ was doped into the crystal structure. The H2 evolution performance over the prepared samples from inorganic/organic sacrificial solution was systematic investigated.

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Structural/Property Relationships for Optical Materials

MRS Proceedings ◽

10.1557/proc-329-215 ◽

1993 ◽

Vol 329 ◽

Author(s):

Vivien D.

Keyword(s):

Crystal Structure ◽

Optical Properties ◽

Electronic Structure ◽

Chemical Composition ◽

Field Strength ◽

Optical Materials ◽

Site Occupancy ◽

Laser Materials ◽

Crystal Field Strength ◽

The Matrix

AbstractIn this paper the relationships between the crystal structure, chemical composition and electronic structure of laser materials, and their optical properties are discussed. A brief description is given of the different laser activators and of the influence of the matrix on laser characteristics in terms of crystal field strength, symmetry, covalency and phonon frequencies. The last part of the paper lays emphasis on the means to optimize the matrix-activator properties such as control of the oxidation state and site occupancy of the activator and influence of its concentration.

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