Visible Light Active Nitrogen and Cobalt Co-doped TiO2 Nanoparticles: Synthesis, Characterization and Photocatalytic Activity

Abstract A facile and room temperature approach to synthesize pure TiO2 and different variants of nirogen and cobalt co-doped TiO2 (CoN-TiO2) catalysts is reported in this study. The successful synthesis and crystalline phase analysis was carried out via X-ray diffraction (XRD) which confirmed anatase phase with tetragonal structure. The spherical morphology, uniform size distribution in the range of 20-40 nm and presence of dopants in final product were validated by scanning electron microscopy (SEM) and Energy dispersive X-ray spectroscopy (EDS). Diffused reflectance spectroscopy (DRS) is deployed for study of optical properties. A reduction in band gap from 3.2 eV for pure TiO2 nanoparticles to 2.34 eV for the 7 wt.%. doped CoN-TiO2 was observed. The photocatlytic activity of pure TiO2, and CoN-TiO2 nanoparticles was studied against methyl orange.The photocatlytic activity of CoN-TiO2 was almost double as compared to undoped TiO2 which proves these catalysts to be very efficient and potential candidate for the wastewater treatment at industrial level.

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Effect of Pulsed Current Frequency and Anodisation Time on Surface Properties of Electropolished and Nonelectropolished Titanium Substrates

International Journal of Corrosion ◽

10.1155/2018/3204301 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8

Author(s):

Victória da Costa Marba ◽

Natal N. Regone ◽

Eduardo N. Codaro ◽

Heloisa A. Acciari

Keyword(s):

Room Temperature ◽

Anatase Phase ◽

Surface Characteristics ◽

Pulsed Current ◽

X Ray Diffraction ◽

Anodic Films ◽

Current Frequency ◽

X Ray ◽

Titanium Substrates ◽

Scanning Electron

Surface characteristics of anodic films formed on electropolished and nonelectropolished titanium substrates have been evaluated using different sets of anodisation parameters at room temperature. Surfaces were analysed by light microscopy, Raman spectroscopy, scanning electron microscopy, and X-ray diffraction. The formation of TiO2 anatase phase was only detected on nonelectropolished substrates and there seems to be a larger amount of anatase as samples are anodised; consequently, the smallest crystals were obtained at the highest frequency of pulsed current. EIS results showed that there is no difference in the degree of compactness along the layer thickness.

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Transparent Conducting TGZO Thin Films Deposited by DC Magnetron Sputtering at Room Temperature

Materials Science Forum ◽

10.4028/www.scientific.net/msf.663-665.1041 ◽

2010 ◽

Vol 663-665 ◽

pp. 1041-1044

Author(s):

Han Fa Liu ◽

Hua Fu Zhang

Keyword(s):

Thin Films ◽

Magnetron Sputtering ◽

Room Temperature ◽

Hexagonal Structure ◽

X Ray Diffraction ◽

Dc Magnetron Sputtering ◽

X Ray ◽

Transparent Conducting ◽

Average Transmittance ◽

Co Doped

Transparent conducting Ti-Ga co-doped zinc oxide (TGZO) thin films with high transmittance, low resistivity were firstly prepared on glass substrate by direct current (DC) magnetron sputtering at room temperature. X-ray diffraction (XRD) and scanning electron microscopy (SEM) show that the TGZO films are polycrystalline with a hexagonal structure and have a preferred orientation along the c-axis perpendicular to the substrate. The lowest resistivity obtained in our experiment is 3.95×10-4Ω⋅cm. The average transmittance of the films is over 92% in the range of 400~760 nm.

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Preparation and Properties of Cupper and Iron Doped TiO2 Nanotubes by Anodization Method

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.744.453 ◽

2017 ◽

Vol 744 ◽

pp. 453-457

Author(s):

Somkuan Photharin ◽

Udom Tipparach

Keyword(s):

Room Temperature ◽

Anatase Phase ◽

Ammonium Fluoride ◽

Deionized Water ◽

Titania Nanotubes ◽

X Ray Diffraction ◽

X Ray ◽

Ordered Arrays ◽

Vis Spectroscopy ◽

Anodization Method

We have synthesized titania nanotubes by an anodization method. The anodization was carried out in a two-electrode configuration bath with Ti sheet as the anode and the Pt as the counter electrode. In this experiment, one face of the Ti foils was exposed to the electrolyte during anodization. The electrolytes were mixtures of ethylene glycol (EG), ammonium fluoride (NH4F) and deionized water (DI water) that contained of Cu and Fe dopants of 0.5 mM. The anodizing voltage was set to 50 V and the anodization was performed at room temperature for 2 h. The nanotubes were crystallized by annealing at 450°C for 2 h. The morphology, structure, and optical properties of the prepared nanotubes were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), and UV-vis spectroscopy (UV-vis) respectively. The results show that titania nanotubes are anatase phase and the nanotubes are arranged in highly ordered arrays.

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Dielectric, ferroelectric and optical properties of Na and Nb co-doped (Bi0.5Na0.5)0.94Ba0.06TiO3

Фізика і хімія твердого тіла ◽

10.15330/pcss.22.4.607-613 ◽

2021 ◽

Vol 22 (4) ◽

pp. 607-613

Author(s):

Asif Ali ◽

Hina Zahid

Keyword(s):

Optical Properties ◽

Solid State ◽

Energy Density ◽

Room Temperature ◽

Optical Band Gap ◽

X Ray Diffraction ◽

X Ray ◽

Solid State Sintering ◽

Cubic Structure ◽

Co Doped

[(Bi0.5Na0.5)0.94Ba0.06]1-xNaTi1-xNbO3 (x = 0.5 and 0.10) ceramics were prepared via conventional solid-state sintering route. X-ray diffraction analysis of the samples exhibited the formation of the cubic structure. Similar structure was observed from the Raman spectra of the samples. The optical band gap of the samples slightly decreased from 3.08 to 3.06 eV with increasing level of Na+ and Nb5+. The addition of Na+ and Nb5+ shifted Tm towards room temperature (RT). The sample x = 0.05 had a stable relative permittivity ɛr(mid) = 3914 across the temperature range 79-350 ℃ and tanδ < 0.025 (104-279 ℃). The energy density of sample with x = 0.05 was 0.4 J/cm3 which decreased to 0.32 J/cm3 at an applied electric field of 50 kV/cm with further substitution of Na+ and Nb5+ (i.e., x = 0.10).

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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Electron Microscope study of commensurate-incommensurate phase transition in BaZnGeO4

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173996 ◽

1990 ◽

Vol 48 (4) ◽

pp. 172-173

Author(s):

Naoki Yamamoto ◽

Makoto Kikuchi ◽

Tooru Atake ◽

Akihiro Hamano ◽

Yasutoshi Saito

Keyword(s):

Phase Transition ◽

Electron Microscope Study ◽

Room Temperature ◽

Hexagonal Lattice ◽

Ferroelectric Materials ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Periodic Arrays ◽

Modulation Wave Vector

BaZnGeO4 undergoes many phase transitions from I to V phase. The highest temperature phase I has a BaAl2O4 type structure with a hexagonal lattice. Recent X-ray diffraction study showed that the incommensurate (IC) lattice modulation appears along the c axis in the III and IV phases with a period of about 4c, and a commensurate (C) phase with a modulated period of 4c exists between the III and IV phases in the narrow temperature region (—58°C to —47°C on cooling), called the III' phase. The modulations in the IC phases are considered displacive type, but the detailed structures have not been studied. It is also not clear whether the modulation changes into periodic arrays of discommensurations (DC’s) near the III-III' and IV-V phase transition temperature as found in the ferroelectric materials such as Rb2ZnCl4.At room temperature (III phase) satellite reflections were seen around the fundamental reflections in a diffraction pattern (Fig.1) and they aligned along a certain direction deviated from the c* direction, which indicates that the modulation wave vector q tilts from the c* axis. The tilt angle is about 2 degree at room temperature and depends on temperature.

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Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

10.26434/chemrxiv.7092263.v1 ◽

2018 ◽

Author(s):

Katherine Marczenko ◽

James Goettel ◽

Gary Schrobilgen

Keyword(s):

Room Temperature ◽

Triphenylphosphine Oxide ◽

Donor Ligands ◽

Mechanical Shock ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination ◽

Xenon Trioxide ◽

Distorted Octahedra ◽

Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO3 was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, the solid [(C6H5)3PO]2XeO3, [(CH3)2SO]3(XeO3)2, and (C5H5NO)3(XeO3)2 adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are air-stable whereas [(CH3)2SO]3(XeO3)2 slowly decomposes over several days and [(CH3)2CO]3XeO3 undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C6H5)3PO]2XeO3 is a distorted square pyramid which provides the first example of a five-coordinate XeO3 adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO3. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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Effect of trytophan as dopant on potassium acid phthalate single crystals

10.31221/osf.io/cn28k ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Single Crystals ◽

Room Temperature ◽

Visible Region ◽

X Ray Diffraction ◽

X Ray ◽

Slow Evaporation Technique ◽

Absorption Studies ◽

Evaporation Technique ◽

Potassium Acid Phthalate ◽

Acid Phthalate

Optically transparent single crystals of potassium acid phthalate (KAP, 0.5 g) 0.05 g and 0.1 g (1 and 2 mol %) trytophan were grown in aqueous solution by slow evaporation technique at room temperature. Single crystal X- ray diffraction analysis confirmed the changes in the lattice parameters of the doped crystals. The presence of functional groups in the crystal lattice has been determined qualitatively by FTIR analysis. Optical absorption studies revealed that the doped crystals possess very low absorption in the entire visible region. The dielectric constant has been studied as a function of frequency for the doped crystals. The thermal stability was evaluated by TG-DSC analysis.

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Structural and Enhanced Optical Properties of Stabilized γ‒Bi2O3 Nanoparticles: Effect of Oxygen Ion Vacancies

Nanomaterials ◽

10.3390/nano10061023 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1023 ◽

Cited By ~ 2

Author(s):

Ashish Chhaganlal Gandhi ◽

Chia-Liang Cheng ◽

Sheng Yun Wu

Keyword(s):

Room Temperature ◽

Excess Oxygen ◽

Ambient Atmosphere ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Band Emission ◽

Oxygen Ion ◽

Integrated Intensity ◽

Effect Of Oxygen

We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.

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Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

MRS Proceedings ◽

10.1557/proc-133-415 ◽

1988 ◽

Vol 133 ◽

Cited By ~ 3

Author(s):

K. S. Kumar ◽

S. K. Mannan

Keyword(s):

High Temperature ◽

Mechanical Alloying ◽

Mechanical Milling ◽

Room Temperature ◽

Crystalline Compound ◽

X Ray Diffraction ◽

X Ray ◽

Β Phase ◽

Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

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