scholarly journals Chemical Structure of TiO2Nanotube Photocatalysts Promoted by Copper and Iron

2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Chang-Yu Liao ◽  
H. Paul Wang ◽  
Hong-Ping Lin
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Chemical Structure ◽  
Visible Light Photocatalysis ◽  
Light Radiation ◽  
Photoexcited Electron ◽  
Edge Structure ◽  
X Ray ◽  
X Ray Absorption

TiO2nanotubes (TNTs) promoted by copper (5%) (Cu-TNT) and iron (5%) (Fe-TNT) were prepared for visible-light photocatalysis. By X-ray absorption near edge structure (XANES) spectroscopy, it is found that the enhanced photocatalytic degradation of methylene blue (MB) on Cu-TNT and Fe-TNT is associated with the predominant surface photoactive sites A2((Ti=O)O4). By extended X-ray absorption fine structure (EXAFS) spectroscopy, the dispersed copper and iron also cause increases in the Ti–O and Ti–(O)–Ti bond distances by 0.01-0.02 and 0.04-0.05 Å, respectively. The decreased Ti–O bonding energy may lead to an increase of photoexcited electron transport. The copper- or-iron promoted TNT can thus enhance photocatalytic degradation of MB under the visible-light radiation.

scholarly journals The Improved Photocatalytic Properties of Methylene Blue for V2O3/CNT/TiO2Composite under Visible Light

2010 ◽  
Vol 2010 ◽  
pp. 1-5 ◽  
Author(s):  
Ming-Liang Chen ◽  
Won-Chun Oh
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Area Measurement ◽  
Bet Surface Area ◽  
Multiwall Carbon Nanotube ◽  
X Ray Diffraction ◽  
Vanadyl Acetylacetonate ◽  
X Ray ◽  
Transmission Electron

Multiwall carbon nanotube (MWCNT), vanadyl acetylacetonate (V(acac)3), and titaniumn-butoxide (TNB) were used as carbon, vanadium oxide, and titanium oxide precursor to prepare V2O3/CNT/TiO2composite. The obtained composite was characterized by BET surface area measurement, X-ray diffraction, transmission electron microscopy, and energy dispersive X-ray analysis. In addition, we used methylene blue (MB) solution under condition of visible light irradiation to determine their photocatalytic degradation efficiency. In conclusion, the V2O3/CNT/TiO2composite had excellent photocatalytic degradation for MB solution under visible light.

scholarly journals In situ X-ray absorption spectroscopic studies of TiO2 photocatalytic active sites for degradation of trace CHCl3 in drinking water

2021 ◽  
Vol 28 (6) ◽  
Author(s):  
T.-L. Hsiung ◽  
L.-W. Wei ◽  
H.-L. Huang ◽  
H. Paul Wang
Keyword(s):  
Drinking Water ◽  
Photocatalytic Degradation ◽  
Active Sites ◽  
Spectroscopic Studies ◽  
Band Gap Energy ◽  
Disinfection Byproducts ◽  
Edge Structure ◽  
X Ray ◽  
X Ray Absorption

Toxic disinfection byproducts such as trihalomethanes (e.g. CHCl3) are often found after chlorination of drinking water. It has been found that photocatalytic degradation of trace CHCl3 in drinking water generally lacks an expected relationship with the crystalline phase, band-gap energy or the particle sizes of the TiO2-based photocatalysts used such as nano TiO2 on SBA-15 (Santa Barbara amorphous-15), TiO2 clusters (TiO2–SiO2) and atomic dispersed Ti [Ti-MCM-41 (Mobil Composition of Matter)]. To engineer capable TiO2 photocatalysts, a better understanding of their photoactive sites is of great importance and interest. Using in situ X-ray absorption near-edge structure (XANES) spectroscopy, the A1 (4969 eV), A2 (4971 eV) and A3 (4972 eV) sites in TiO2 can be distinguished as four-, five- and six- coordinated Ti species, respectively. Notably, the A2 Ti sites that are the main photocatalytic species of TiO2 are shown to be accountable for about 95% of the photocatalytic degradation of trace CHCl3 in drinking water (7.2 p.p.m. CHCl3 gTiO2 −1 h−1). This work reveals that the A2 Ti species of a TiO2-based photocatalyst are mainly responsible for the photocatalytic reactivity, especially in photocatalytic degradation of CHCl3 in drinking water.

scholarly journals Radiation chemistry of molecular compounds and polymers by soft X-ray spectroscopy and microscopy

2017 ◽  
Vol 95 (11) ◽  
pp. 1191-1197
Author(s):  
Jianjun Yang ◽  
Jian Wang
Keyword(s):  
Mass Loss ◽  
Chemical Structure ◽  
Molecular Complexes ◽  
Large Mass ◽  
Radiation Chemistry ◽  
Edge Structure ◽  
X Ray ◽  
Structure Changes ◽  
X Ray Absorption ◽  
Molecular Compounds

Soft X-ray-induced radiation chemistry in selected Fe molecular compounds and some aliphatic polymers was studied using soft X-ray absorption spectroscopy, and scanning transmission X-ray microscopy. X-ray absorption near-edge structure (XANES) spectroscopy was used to elucidate the radiation chemistry. The results show that damage to the Fe molecular complexes involves Fe-ligand bond breaking, ligand damage, and subsequent photoreduction of Fe(III) if it is not tightly bonded to oxygen. Upon radiation damage, polymer PAN primarily undergoes chemical structure changes without mass loss, PECA experiences chemical structure changes as well as small mass loss, while PPC and PEC suffer large mass loss with chemical structure changes. These studies are not only important to X-ray analysis of radiation sensitive materials but also are valuable to the applications of X-ray lithography and other types of nanofabrication involving photoresist.

Visible-Light Driven Effective Photocatalytic Degradation of Methylene Blue Dye Using Perforated Curly Zn0.1Ni0.9O Nanosheets

2020 ◽  
Vol 20 (9) ◽  
pp. 5759-5764
Author(s):  
V. Karthikeyan ◽  
G. Gnanamoorthy ◽  
P. Varun Prasath ◽  
V. Narayanan ◽  
Suresh Sagadevan ◽  
...  
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Organic Waste ◽  
Hydrothermal Process ◽  
Blue Dye ◽  
Cubic Phase ◽  
X Ray Diffraction ◽  
X Ray ◽  
Visible Light Driven

Herein, we report the facile synthesis, characterization and visible-light-driven photocatalytic degradation of perforated curly Zn0.1Ni0.9O nanosheets synthesized by hydrothermal process. The X-ray diffraction (XRD) and scanning electron microscopy (SEM) studies confirmed the cubic phase crystalline structure and growth of high density perforated curly Zn0.1Ni0.9O nanosheets, respectively. As a photocatalyst, using methylene blue (MB) as model pollutant, the synthesized nanosheets demonstrated a high degradation efficiency of ~76% in 60 min under visible light irradiation. The observed results suggest that the synthesized Zn0.1Ni0.9O nanosheets are attractive photocatalysts for the degradation of toxic organic waste in the water under visible light.

Influence of rare-earth metal on the zinc oxide nanostructures: application in the photocatalytic degradation of methylene blue and p-nitro phenol

2018 ◽  
Vol 7 (4) ◽  
pp. 360-371 ◽  
Author(s):  
Prakash K. Labhane ◽  
Gunvant H. Sonawane ◽  
Shirish H. Sonawane
Keyword(s):  
Methylene Blue ◽  
Zinc Oxide ◽  
Photocatalytic Activity ◽  
Rare Earth ◽  
Photocatalytic Degradation ◽  
Uv Light ◽  
Light Radiation ◽  
Spherical Nanoparticles ◽  
X Ray ◽  
Doped Zno

Abstract Rare-earth cerium (Ce)-doped zinc oxide (ZnO) spherical nanoparticles were synthesized by using the co-precipitation method. The doped materials were characterized by means of the X-ray diffraction, Williamson-Hall Plot, and field emission scanning electron microscopy analyses. The prepared nanoparticles exhibit a hexagonal wurtzite structure as observed from the XRD measurements. Energy dispersive X-ray spectroscopy data confirmed the purity of the prepared samples. The photocatalytic activity of the rare-earth Ce-doped ZnO spherical nanoparticles was investigated through the degradation of methylene blue (MB) and p-nitrophenol (PNP) solution under UV light radiation. Among the different amounts of dopant, 5 mole% Ce-doped ZnO nanoparticles showed the highest degradation with UV light radiation for both MB dye and PNP solution. The particle size, morphology, and separation of the photo-induced electron–hole pair are the main factors that influence photocatalytic activity. The probable mechanisms of photocatalytic degradation and mineralization of MB and PNP are also explained by liquid chromatography–mass spectrometry analysis.

Chemical and orientational imaging of polymeric samples

1994 ◽  
Vol 52 ◽  
pp. 68-69
Author(s):  
H. Ade ◽  
B. Hsiao ◽  
G. Mitchell ◽  
E. Rightor ◽  
A. P. Smith ◽  
...  
Keyword(s):  
Ethylene Terephthalate ◽  
National Laboratory ◽  
Brookhaven National Laboratory ◽  
Carbonyl Groups ◽  
Aromatic Rings ◽  
Edge Structure ◽  
X Ray ◽  
Scanning Transmission ◽  
Polymeric Samples ◽  
X Ray Absorption

We have used the Scanning Transmission X-ray Microscope at beamline X1A (X1-STXM) at Brookhaven National Laboratory (BNL) to acquire high resolution, chemical and orientation sensitive images of polymeric samples as well as point spectra from 0.1 μm areas. This sensitivity is achieved by exploiting the X-ray Absorption Near Edge Structure (XANES) of the carbon K edge. One of the most illustrative example of the chemical sensitivity achievable is provided by images of a polycarbonate/pol(ethylene terephthalate) (70/30 PC/PET) blend. Contrast reversal at high overall contrast is observed between images acquired at 285.36 and 285.69 eV (Fig. 1). Contrast in these images is achieved by exploring subtle differences between resonances associated with the π bonds (sp hybridization) of the aromatic groups of each polymer. PET has a split peak associated with these aromatic groups, due to the proximity of its carbonyl groups to its aromatic rings, whereas PC has only a single peak.

Visible Light Active Ce-doped TiO2 Nanoparticles for Photocatalytic Degradation of Methylene Blue

2016 ◽  
Vol 13 (1) ◽  
pp. 110-116 ◽  
Author(s):  
Rani P. Barkul ◽  
Farah-Naaz A. Shaikh ◽  
Sagar D. Delekar ◽  
Meghshyam K. Patil
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Tio2 Nanoparticles ◽  
Doped Tio2 ◽  
Visible Light Active

Full-Field Calcium K-Edge X-ray Absorption Near-Edge Structure Spectroscopy on Cortical Bone at the Micron-Scale: Polarization Effects Reveal Mineral Orientation

2016 ◽  
Vol 88 (7) ◽  
pp. 3826-3835 ◽  
Author(s):  
Bernhard Hesse ◽  
Murielle Salome ◽  
Hiram Castillo-Michel ◽  
Marine Cotte ◽  
Barbara Fayard ◽  
...  
Keyword(s):  
Cortical Bone ◽  
Edge Structure ◽  
Full Field ◽  
Polarization Effects ◽  
X Ray ◽  
X Ray Absorption

scholarly journals Fabrication of AgCl/Ag3PO4/graphitic carbon nitride heterojunctions for enhanced visible light photocatalytic decomposition of methylene blue, methylparaben and E. coli

RSC Advances ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 6383-6394 ◽  
Author(s):  
Haishuai Li ◽  
Linlin Cai ◽  
Xin Wang ◽  
Huixian Shi
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Photocatalytic Degradation ◽  
Visible Light Irradiation ◽  
Carbon Nitride ◽  
Light Irradiation ◽  
Graphitic Carbon Nitride ◽  
Photocatalytic Decomposition ◽  
E Coli ◽  
Visible Light Photocatalytic

A noval ternary nanocomposite AgCl/Ag3PO4/g-C3N4 was successfully synthesized for photocatalytic degradation of methylene blue, methylparaben and inactivation of E. coli under visible light irradiation, showing excellent photocatalytic degradation performance and stability.

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