Degradation of phenol by using magnetic photocatalysts of titania

2013 ◽  
Vol 67 (7) ◽  
pp. 1434-1441 ◽  
Author(s):  
Chiung-Fen Chang ◽  
I.-Peng Tseng
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
Single Phase ◽  
Health Impacts ◽  
X Ray Diffraction ◽  
Final Temperature ◽  
Soaking Time ◽  
X Ray ◽  
Green Materials ◽  
Diffraction Patterns

Magnetic TiO2 (MT) composites were prepared and applied to degrading phenol, which is one of the listed priority pollutants. The effects of heat treatment under preparation on the photocatalytic activity of MT composites have been investigated by varying the soaking time under a constant final temperature of 823 K. The total organic carbon and ring-remaining intermediates of o-DHB, p-DHB and 1,4-BQ in solution were detected during the photodegradation of phenol. All the resulting MT composites were the single-phase anatase and magnetite judged by X-ray diffraction patterns. The calcination of the as-prepared particles was proven to be extremely crucial to the photocatalytic activity. The best condition of heat treatment was found to be soaking time of 2 h at T = 823 K due to the good performance of photocatalytic activity, stable magnetic property, and reusability over three times. The results lead to the conclusion that recyclable MT composites prepared in this study, which belonged to the category of recyclable green materials, exhibit good photocatalytic activity to degrade phenol so as to possess applicable potential for the degradation of refractory organics in the aqueous solution. Furthermore, the environmental and health impacts were reduced as MT composites were applied in the treatment of water pollution.

scholarly journals Ferromagnetic Order in the Intermetallic Alloys laNi5-xMgx

2012 ◽  
Vol 29 (1) ◽  
pp. 50
Author(s):  
D.N Ba ◽  
L.T Tai ◽  
N.T Trung ◽  
N.T Huy
Keyword(s):  
Magnetic Properties ◽  
Curie Temperature ◽  
Room Temperature ◽  
Single Phase ◽  
Chemical Doping ◽  
Intermetallic Alloys ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ferromagnetic Order ◽  
Diffraction Patterns

The influences of the substitution of Ni with Mg on crystallographic and magnetic properties of the intermetallic alloys LaNi5-xMgx (x ≤ 0.4) were investigated. The X-ray diffraction patterns showed that all samples were of single phase, and the lattice parameters, a and c, decreased slightly upon chemical doping. LaNi5 is well known as an exchange-enhanced Pauli paramagnet. Interestingly, in LaNi5-xMgx, the ferromagnetic order existed even with a small amount of dopants; the Curie temperature reached the value of room temperature for x = 0.2, and enhanced with increasing x.

Analysis of Selected Area Diffraction Patterns With Winjade

1998 ◽  
Vol 4 (S2) ◽  
pp. 342-343 ◽  
Author(s):  
S. D. Walck ◽  
P. Ruzakowski-Athey
Keyword(s):  
Single Phase ◽  
Xrd Analysis ◽  
Analysis Program ◽  
X Ray Diffraction ◽  
Program Module ◽  
Vast Number ◽  
One Dimensional ◽  
X Ray ◽  
Diffraction Patterns ◽  
Xrd Patterns

The analysis of Selected Area Diffraction (SAD) patterns that are collected from a single phase material having sufficient crystallites to provide continuous rings is relatively straightforward. However, when this condition is not met and there may be several phases present having rings of a spotty nature, the pattern is complex and can be quite difficult to analyze manually because of the vast number of discrete spots. WinJade from MDI is an X-ray diffraction (XRD) analysis program with an Electron Diffraction Program Module (EDPM) that can be used to aid in the analysis of SAD patterns. The EDPM produces Integrated Circular Density Plots (ICDP), which are one-dimensional intensity profiles plotted as a function of equivalent XRD 20 values or crystal d-spacings. These ICDP's can be overlayed with XRD patterns or with reference lines from the NIST and JCPDS crystalline databases for direct comparisons.

Preparation of Heterojunction Semiconductor SnS2/SnO2 with Enhanced Photocatalytic Properties

2013 ◽  
Vol 316-317 ◽  
pp. 1059-1062 ◽  
Author(s):  
Ping Chen ◽  
Ming Sheng Qin ◽  
Fu Qiang Huang
Keyword(s):  
Photocatalytic Activity ◽  
Single Phase ◽  
Near Infrared ◽  
Photocatalytic Performance ◽  
Chemical Compositions ◽  
X Ray Diffraction ◽  
Simple Method ◽  
X Ray ◽  
Structure Morphology ◽  
Nir Absorption

The Formation of Heterojunction Structure between Two Semiconductors Was Considered as an Effective Method to Enhance the Photocatalytic Activity. here, we Reported a Simple Method to Prepare SnS2/SnO2Heterojunction Photocatalysts by Annealing SnS2in Air. the Structure, Morphology, Chemical Compositions and Optical Properties of the Obtained Materials Were Characterized by the X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Energy-dispersive X-ray Spectroscopy (EDX) and Ultraviolet-visible-near Infrared (UV-Vis-NIR) Absorption Spectra. the Photocatalytic Investigations Showed the Composites Have Higher Photocatalytic Activity than the Single-phase SnS2. the SnS2Powder which Annealed at 400 °C for 60 Min Showed the Highest Photocatalytic Performance.

A second occurrence of lyndochite

1965 ◽  
Vol 34 (268) ◽  
pp. 237-248 ◽  
Author(s):  
J. E. T. Horne ◽  
J. R. Butler
Keyword(s):  
Heat Treatment ◽  
Rare Earth ◽  
Peak Concentration ◽  
Type Locality ◽  
X Ray Diffraction ◽  
X Ray ◽  
Suitable Heat Treatment ◽  
Diffraction Patterns ◽  
The Many ◽  
Almost All

SummaryLyndochite from Tura dukas, 35 miles north of Nanyuki, Kenya, agrees closely with the type material from Canada in its chemical analysis, in the distribution of the rare earths, and in X-ray diffraction data for powder after heat treatment. The mineral is compared and contrasted with aeschynite. Uranium-poor euxenite is intimately associated with lyndochite at the type locality.Since its discovery over thirty-five years ago, lyndochite has remained unrecorded outside its type locality of Lyndoch Township in Ontario, Canada. Its distinctive chemical composition sets it apart from almost all other Ti-rich metamiet niobates and, despite the many analyses that have been made on rare-earth niobate-tantalates, specimens that could have been regarded as similar to or approximating to lyndochite have rarely been mentioned. Its unusual characteristics include high ThO2 (about 10%) and appreciable rare-earth oxides (about 20%) with a lanthanon assemblage showing a peak concentration of Nd (and Ce), rather than any of the heavy lanthanons. The proportions of TiO2 (about 20%) and (Nb,Ta)2O5 (about 40%) are comparable to those in numerous niobate-tantalates, but are only associated with the percentages of ThO2 and Re2O3 mentioned above in some members of the aesehynite-priorite series. The lyndochite now described is chemically very close indeed to the Canadian lyndochite, and both specimens give closely similar X-ray diffraction patterns (after suitable heat treatment) which are distinct from those of any other metamict mineral.

Synthesis of Silicon- and Carbonate-doped Biomimetic Hydroxyapatite in the Presence of Citrate Ions and its Physicochemical, Bioactivity Properties

2020 ◽  
Vol 47 ◽  
pp. 1-12
Author(s):  
Viet Hung Hoang ◽  
Mikhail Aleksandrovich Troubitsin ◽  
Liubov Vladimirovna Furda ◽  
Thi Tham Hong Nguyen
Keyword(s):  
Single Phase ◽  
Physiological Saline ◽  
Degree Of Crystallinity ◽  
Synthesis Process ◽  
X Ray Diffraction ◽  
Soaking Time ◽  
X Ray ◽  
Sbf Solution ◽  
Biomimetic Hydroxyapatite ◽  
Citrate Ions

The present study investigated the phase composition, the structural, morphological, and bioactivity properties of silicon- and carbonate-doped biomimetic hydroxyapatite synthesized by precipitation from aqueous solutions in the presence of different amounts of citrate ions. The X-ray diffraction and Fourier transform infrared spectroscopy analyses confirmed that all the samples exhibited single-phase. Base on the results of the morphological study, all the obtained samples consisted of porous agglomerated particles made up of tiny crystallites in the nanometer range. The change in structural order, as well as the decrease in particle size and degree of crystallinity result from the presence of citrate ions were revealed by X-ray diffraction, dynamic light scattering, and scanning electron microscopy analyses. Bioactivity properties of samples were studied by analyzing their bioresorbability in physiological saline (ω (NaCl) = 0.9%) and evaluating their solubility in SBF solution after a certain period of soaking time. The amount of the released Ca2+ ions was found to increase with the increasing concentration of citrate ions introduced in the synthesis process. The better solubility of material with the presence of citrate ions was beneficial in the growth of apatite on its surface that made produced material more biocompatible.

The Effects of Solvents on the Solvothermal Synthesis of BiVO4 Photocatalyst Powders

2015 ◽  
Vol 659 ◽  
pp. 154-158
Author(s):  
N. Thanomsri ◽  
C. Mongkolkachit ◽  
T. Sato ◽  
X. Wu ◽  
Pornapa Sujaridworakun
Keyword(s):  
Heat Treatment ◽  
Photocatalytic Activity ◽  
Visible Light ◽  
Surface Area ◽  
X Ray Diffraction ◽  
Photo Degradation ◽  
X Ray ◽  
Structure Surface ◽  
Xrd Patterns ◽  
Visible Light Photocatalytic

In this study, the effects of different solvents such as ethanol, ethylene glycol, glycerol on the preparation of BiVO4 via solvothermal process, and the influent of calcination heat treatment were studied. The crystal structure, surface area, morphology and optical properties of the obtained BiVO4 particles were investigated by means of X-ray Diffraction (XRD), Brunauer Emmett Teller method (BET), Scanning electron microscope (SEM) and UV-Vis reflectance spectroscopy (UV-Vis DRS), respectively. XRD patterns reveal that all of the obtained BiVO4 samples prepared by solvothermal at 130°C for 4 h have monoclinic structure. The UV-Vis DRS demonstrates that the band gaps of prepared BiVO4 are about 2.38-2.40 eV. The photocatalytic activity was evaluated by photo-degradation of rhodamine B (Rh B) solution under visible light irradiation (λ>420 nm). As the results, the BiVO4 prepared by using ethanol having high crystallinity and surface area showed the highest visible light photocatalytic activity compared to using glycerol and ethylene glycerol, respectively. Furthermore, the photocatalytic activity of BiVO4 prepared by using ethylene glycerol and glycerol could be enhanced by calcination heat treatment at 500°C for 2 h.

Reduced-pressure MOCVD of highly crystalline BaTiO3 thin films

1992 ◽  
Vol 7 (3) ◽  
pp. 542-545 ◽  
Author(s):  
Peter C. Van Buskirk ◽  
Robin Gardiner ◽  
Peter S. Kirlin ◽  
Steven Nutt
Keyword(s):  
Thin Films ◽  
Electron Diffraction ◽  
Total Pressure ◽  
Single Phase ◽  
X Ray Diffraction ◽  
Reduced Pressure ◽  
X Ray ◽  
Selected Area Electron Diffraction ◽  
Diffraction Patterns ◽  
First Time

Epitaxial BaTi3 films have been grown on NdGaO3 [100] substrates by reduced pressure MOCVD for the first time. The substrate temperature was 1000 °C and the total pressure was 4 Torr. Electron and x-ray diffraction measurements indicate highly textured, single phase films on the NdGaO3 substrate which are predominantly [100], with [110] also present. TEM and selected area electron diffraction (SAED) indicate two specific orientational relationships between the [110] and the [001] diffraction patterns.

THE XRD STUDY OF THE EFFECT OF SLIGHT CHANGE IN STRUCTURE ON THE SUPERCONDUCTIVITY OF Y-Ba-Cu-O SYSTEM MATERIAL

1987 ◽  
Vol 01 (07n08) ◽  
pp. 289-293 ◽  
Author(s):  
WANG HUAQIN ◽  
ZHANG SHIYUAN ◽  
JIN TONGZHENG ◽  
HAN SHIYING ◽  
QIU DIRONG ◽  
...  
Keyword(s):  
Single Phase ◽  
Crystal Symmetry ◽  
Epr Spectra ◽  
Processing Conditions ◽  
X Ray Diffraction ◽  
X Ray ◽  
Xrd Study ◽  
The Difference ◽  
Diffraction Patterns ◽  
Flowing Oxygen

In this paper the differences in diffraction intensities from some crystal planes in the X-ray diffraction patterns of high Tc Y-Ba-Cu-O system superconductors prepared by different processing conditions and the difference among various structure cells in references are interpreted using computer fitting. The results suggest that there exists two structure cells in the single phase YBa2Cu3O7−x samples. Both structure cells have the same crystal symmetry and almost the same lattice parameters, a=3.821Å, b=3.892Å and c=11.676Å, but the different distortion degree of Cu2-O plane. According to EPR spectra measured on the same samples, it is considered that the improvement of superconductivity for the samples prepared by two-step annealing in flowing oxygen may be related to concentration of the structure cell with more serious distortion on the Cu2-O plane.

Photocatalytic Activity of SrAl2O4:xCu Powders under Solar Irradiation

2017 ◽  
Vol 16 ◽  
pp. 63-66 ◽  
Author(s):  
Aurora Berlanga ◽  
Reyes Garcia-Diaz ◽  
Carlos Rodriguez Garcia ◽  
Jorge Oliva ◽  
Maria Teresa Romero ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Monoclinic Phase ◽  
Combustion Method ◽  
Solar Irradiation ◽  
X Ray Diffraction ◽  
X Ray ◽  
Dye Pollutants ◽  
Diffraction Patterns ◽  
Absorbance Band

Cooper doped SrAl2O4:xCu powders were synthesized by combustion method. The doping concentrations were x= 0.1%, 0.3%, 0.5%, and 1.0 at.%. X-ray diffraction patterns indicate that all Cu doped/undoped powders has monoclinic phase. Also, TEM images show that the size of the nanoparticles decreases as the content of Cu increases. The photocatalytic degradation of Congo red (CR) was studied by monitoring intensity of its characteristic absorbance band centered at 494 nm. The best result was obtained with the 0.1% Cu doped sample, since it degraded 100% of CR after 120 minutes under sunlight excitation. Hence, our results suggest that SrAl2O4:xCu powders could be suitable candidates for photocatalytic degradation of dye pollutants under sunlight.

STRUCTURE AND PROPERTIES OF (La2-xSrx)MnO4 COMPOUNDS

2005 ◽  
Vol 19 (01n03) ◽  
pp. 541-548
Author(s):  
M. S. WU ◽  
H.-C. I. KAO ◽  
H. S. SHEU ◽  
Y. P. CHIANG ◽  
L. HORNG ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Single Phase ◽  
Perovskite Phase ◽  
Treatment Temperature ◽  
X Ray Diffraction ◽  
Solubility Range ◽  
Jahn Teller ◽  
Jahn Teller Effect ◽  
Higher Temperature ◽  
Diffraction Patterns

Polycrystalline single phase ( La 2-x Sr x) MnO 4 (1.10≤ x ≤1.40) samples were prepared by a citrate precursor method. They have tetragonal K 2 NiF 4 structure with a space group of 14/mmm, increasing x, unit-cell a-axis increases and c-axis decreases, which is a result of decreasing of the Jahn-Teller effect due to the increase of the Mn ( IV ) ion. Spin glass state exists at low temperature and a hump observed from the susceptibility (χ) measurement is probably caused by the interactions of several magnetic phases. Among them, ( La 0.6 Sr 1.4) MnO 4 has the largest magnetoresistance ratio ([ρ(H)-ρ(0)]/ρ(0)), which reaches to 78.4% at 48 K. It is not possible to obtain single phase materials with 0.60≤ x ≤1.00 in the heat treatment temperature range of 1000-1600°C. Impurities were easily observed under SEM and X-ray diffraction patterns. Increasing the heating period and decreasing the temperature, the amount of ABO3 perovskite phase increases. In order to extend the solubility range, of the SrO in the ( La 2-x Sr x) MnO 4, it probably needs a higher temperature (>1600°C) and a shorter heat treatment period (<1 h).

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