scholarly journals Ce/Mo metal oxides synthesized with DBD plasma as efficient photocatalysts: Effect of Ce/Mo molar ratios

2021 ◽  
Vol 261 ◽  
pp. 02038
Author(s):  
Kangkang Zheng ◽  
Xumei Tao
Keyword(s):  
Metal Oxides ◽  
Photocatalytic Performance ◽  
Barrier Discharge ◽  
Uv Light ◽  
Molar Ratio ◽  
Dye Wastewater ◽  
Surface Chemical ◽  
Dbd Plasma ◽  
Molar Ratios ◽  
First Time

Ce/Mo metal oxides with different Ce/Mo molar ratios were synthesized via dielectric barrier discharge (DBD) method for the first time and applied as efficient photocatalysts. The morphology and physicochemical properties of the synthesized samples were characterized by XRD, SEM, BET and XPS. Ce/Mo metal oxides synthesized with Ce(NO3)3·6H2O and (NH4)6Mo7O24·4H2O molar ratio of 4:1 exhibited more surface chemical adsorption of oxygen, which were beneficial to the photocatalytic performance. The degradation rate of 1000 mL (50 mg/L) methyl orange could reach 80% within 18 min under UV-light radiation. Ce/Mo metal oxides exhibited excellent photocatalytic performance and had potential application prospect in dye wastewater treatment.

scholarly journals Enhanced Photodecomposition of Methylene Blue in Water with Sr1−xKxTiO3−δ@PC-polyHIPEs under UV and Visible Light

2018 ◽  
Vol 2018 ◽  
pp. 1-10 ◽  
Author(s):  
Yonghua Gao ◽  
Tao Zhang ◽  
Qipeng Guo ◽  
Lizhen Gao
Keyword(s):  
Methylene Blue ◽  
Visible Light ◽  
Room Temperature ◽  
Oxygen Vacancies ◽  
Photocatalytic Performance ◽  
Uv Light ◽  
Water Solution ◽  
Internal Phase ◽  
Water Pollutant ◽  
First Time

Photocatalytic method was investigated to remove water pollutant methylene blue (MB) produced in textile, plastic, and dye industries. PC-polyHIPEs were prepared by light-induced polymerization of dopamine in transparent polyHIPEs which were synthesized by polymerization within high internal phase emulsions. Sr1-xKxTiO3-δ (x = 0–0.5) nanoparticles were incorporated and adhered to PC-polyHIPEs to form Sr1-xKxTiO3-δ@PC-polyHIPEs for the first time. The catalysts were characterized by XRD, FTIR, TGA, UV-Vis DRS, and SEM and their photocatalytic properties for MB decomposition were measured over UV-Vis spectrometer. The PC-polyHIPEs were of interconnected porous structure with around 100 μm pores and 30 μm windows. Sr1−xKxTiO3−δ@PC-polyHIPEs showed excellent MB decomposition activity under either UV or visible light although Sr1−xKxTiO3−δ alone worked only under UV light. When x = 0.3, Sr1−xKxTiO3−δ@PC-polyHIPEs showed the highest photocatalytic performance due to the existence of more oxygen vacancies. When the water solution with 50 mg L−1 MB and 1.6 gcat. L−1 Sr0.7K0.3TiO3−δ@PC-polyHIPEs was exposed to visible light for 160 min at room temperature, 88.3% of MB was decomposed. After being used for eight cycles, 87.6% activity of fresh Sr0.7K0.3TiO3−δ@PC-polyHIPEs still remained. The influences of salinity, temperature, and catalyst concentration on the catalytic activity were studied. For MB decomposition under visible light, the activation energy of Sr0.7K0.3TiO3−δ@PC-polyHIPEs was calculated to be 12.3 kJ mol−1 and the kinetics analysis revealed that the photocatalysis followed the second-order reaction. These findings demonstrated that Sr1−xKxTiO3−δ@PC-polyHIPEs were an effective candidate for real application in decomposition of MB in water.

scholarly journals The Application of Dielectric Barrier Discharge Plasma on Fischer-Tropsch Synthesis: A Review

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Teuku Mukhriza ◽  
Hartati Oktarina
Keyword(s):  
Dielectric Barrier Discharge ◽  
Barrier Discharge ◽  
Bubble Column ◽  
Fixed Bed ◽  
Liquid Hydrocarbon ◽  
Dbd Plasma ◽  
Fischer Tropsch ◽  
Dielectric Barrier ◽  
Molar Ratios ◽  
Ft Synthesis

Fischer-Tropsch (FT) Synthesis has been widely known for centuries as the process of converting syngas to liquid fuels. Several reactors including Slurry bubble column, fluidized-bed, and fixed bed reactors have been used for FTS on an industrial scale. Although science has seen remarkable development in technology for FT synthesis, the industry still faces challenges in optimizations of process parameters and achieved desired selectivity.  Extensive research has been continuously conducted to seek the best FT reactor offering heat uniformity and efficient heat transfer across the reactor to increase the catalytic activity and its lifetime. Dielectric Barrier Discharge (DBD) plasma has become one of the options to deal with these issues. This reactor work under low temperature delivers a synergistic effect between plasma and catalyst to break H2 and CO bond. DBD plasma is also suitable for feedstock with high H2/CO molar ratios. It is also found that FT catalyst such as cobalt catalyst used in DBD plasma was well dispersed on the support which in turn favour the selectivity toward liquid hydrocarbon.

scholarly journals Improved adsorption and degradation performance by S-doping of (001)-TiO2

2019 ◽  
Vol 10 ◽  
pp. 2116-2127 ◽  
Author(s):  
Xiao-Yu Sun ◽  
Xiao Sun ◽  
Xian Zhang ◽  
Ni-Xian Qian ◽  
Min Wang ◽  
...  
Keyword(s):  
Oxygen Vacancies ◽  
Photocatalytic Performance ◽  
Lattice Distortion ◽  
Synergistic Effects ◽  
Chemical Vapor ◽  
Surface Chemical ◽  
Ionic Radii ◽  
Thermal Chemical Vapor Deposition ◽  
Molar Ratios ◽  
Chemical States

In this work, sulfur-doped (S-doped) TiO2 with the (001) face exposed was synthesized by thermal chemical vapor deposition at 180 or 250 °C using S/Ti molar ratios R S/Ti of 0, 0.5, 1, 2, 3, 4 and 5. The S-doped samples synthesized at 250 °C exhibit a significantly improved photocatalytic performance. More precisely, S-doping has the following effects on the material: (1) S can adopt different chemical states in the samples. Specifically, it exists in the form of S2− replacing O2− at a ratio of R S/Ti = 1 and also in the form of S6+ replacing Ti4+ at R S/Ti ≥ 2. As a result, S-doping causes a lattice distortion, because the ionic radii of S2− and S6+ differ from that of the O2− and Ti4+ ions. (2) S-doping increases the adsorption coefficient A e for methylene blue (MB) from 0.9% to 68.5% due to the synergistic effects of the oxygen vacancies, increased number of surface chemical adsorption centers as a result of SO4 2− adsorption on the TiO2 surface and the larger pore size. (3) S-doping increases the MB degradation rate from 6.9 × 10−2 min−1 to 18.2 × 10−2 min−1 due to an increase in the amount of •OH and •O2− radicals.

scholarly journals Chemical Speciation of Aluminum in Wine by LC–ICP–MS

Molecules ◽  
2020 ◽  
Vol 25 (5) ◽  
pp. 1069 ◽  
Author(s):  
Katarzyna Karaś ◽  
Anetta Zioła-Frankowska ◽  
Marcin Frankowski
Keyword(s):  
Ph Value ◽  
Human Life ◽  
Daily Intake ◽  
Speciation Analysis ◽  
Gradient Elution ◽  
Molar Ratio ◽  
Molar Ratios ◽  
Icp Ms ◽  
Chemical Equilibrium Modeling ◽  
First Time

Aluminum is very common in the natural environment and in everyday human life. We are living in the “aluminum age.” Its average daily intake should not exceed a few mg/day. Unfortunately, despite the growing number of alarming data about the toxicity of this element, human exposure to aluminum is constantly increasing. The toxicity and bioavailability of aluminum depends mainly on the form in which it occurs. The main variables conditioning the form are the concentration, the type, the molar ratio of aluminum to ligand, the pH value, and the temperature. This research presents a new method for speciation analysis of both inorganic and organic aluminum complexes in model solutions by LC–ICP–MS. Different solutions with variable pH values and different Al/ligand molar ratios (fluorides and several organic ligands, e.g., citrates and oxalates ions) were used. The chromatographic separation process was carried out based on isocratic and gradient elution, using a cation exchange analytical column. All determinations have been confirmed based on chemical equilibrium modeling programs. The new developed method was successfully applied for the first time in speciation analysis of real samples: white and red wine.

Investigation of Antibacterial Property and Photocatalytic Activity of Recyclable Ag/ZnOw Composites

2014 ◽  
Vol 472 ◽  
pp. 831-834
Author(s):  
Jie Wang ◽  
Xiao Yong Pan ◽  
Ling Peng ◽  
Yu Liu ◽  
Nian Jie Wang
Keyword(s):  
Silver Nanoparticles ◽  
Photocatalytic Performance ◽  
Antibacterial Property ◽  
Photocatalytic Property ◽  
Molar Ratio ◽  
Structure And Properties ◽  
Simple Method ◽  
Molar Ratios ◽  
Photocatalytic Activities ◽  
Oxide Whisker

Silver-deposited zinc oxide whisker (Ag/ZnOw) composites with different Ag/Zn molar ratios (MRs) were successfully synthesized by a simple method. Subsequently, the structure and properties of these composites were characterized using various tests. It is found that the silver nanoparticles are located on the root of ZnOw, which is beneficial for the antibacterial and photocatalytic performance of ZnOw. The Ag/ZnOw composite exhibits better antibacterial and photocatalytic activities than that of the pure ZnOw, and the efficiency of both properties increase with increasing molar ratio of Ag/Zn. Moreover, the mechanism which governs the photocatalytic property of the composite has also been discussed thoroughly.

MgO-based nanosheets loaded with ZnxMg1−xO nanoparticles with UV light-driven photocatalytic performance

2017 ◽  
Vol 10 (06) ◽  
pp. 1750072 ◽  
Author(s):  
Junshu Wu ◽  
Linlin Wang ◽  
Jinshu Wang ◽  
Yucheng Du ◽  
Yongli Li
Keyword(s):  
Photoelectron Spectroscopy ◽  
Photocatalytic Performance ◽  
Uv Light ◽  
Controlled Synthesis ◽  
Dye Wastewater ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Light Irradiation ◽  
Uv Visible ◽  
High Temperature Calcination

This paper reports the synthesis of MgO-based nanosheets loaded with UV-light absorbed, wurtzite ZnxMg[Formula: see text]O nanoparticles based on calcining Zn[Formula: see text]-adsorbed Mg(OH)2 precursor, as evidenced by X-ray diffraction, UV-visible, X-ray photoelectron spectroscopy analyses, etc. The surface modification of magnesium oxide (MgO) sheet-like adsorbents by Zn–Mg–O alloys generates photocatalytic activity for the degradation removal of cationic dye Rhodamine B and anionic dye methyl orange under UV light irradiation. These findings provide a route to chemically controlled synthesis of new and highly robust MgO–ZnxMg[Formula: see text]O materials for water purification. The endowed photocatalysis function of MgO makes it be easily recovered via photodegradation of adsorbed dyes rather than high-temperature calcination, thus extending the applications of MgO in dye wastewater treatment.

scholarly journals Surface modification of ZnMgAl-coated steel by dielectric-barrier discharge plasma

RSC Advances ◽  
2019 ◽  
Vol 9 (60) ◽  
pp. 35077-35088 ◽  
Author(s):  
Steffen Knust ◽  
Andreas Kuhlmann ◽  
Teresa de los Arcos ◽  
Guido Grundmeier
Keyword(s):  
Discharge Plasma ◽  
Barrier Discharge ◽  
Alloy Coating ◽  
Coated Steel ◽  
Surface Chemical ◽  
Dielectric Barrier Discharge Plasma ◽  
Dbd Plasma ◽  
Adhesive Properties ◽  
Dielectric Barrier ◽  
Barrier Discharge Plasma

Correlation between atmospheric DBD plasma-induced surface chemical changes on a ZnMgAl alloy coating and the resulting adhesive properties.

4 Pattern Recognition for Healing Burns to Compute Evidence: Space Syntax and Machine Learning Analysis of Burns Center Karachi

2013 ◽  
Vol 1 (1) ◽  
pp. 13
Author(s):  
Javaria Manzoor Shaikh ◽  
JaeSeung Park
Keyword(s):  
Pattern Recognition ◽  
Prediction Models ◽  
Uv Light ◽  
Healing Process ◽  
Space Syntax ◽  
Depth Map ◽  
Routine Tasks ◽  
Hyper Plane ◽  
First Time ◽  
Learning Analysis

Usually elongated hospitalization is experienced byBurn patients, and the precise forecast of the placement of patientaccording to the healing acceleration has significant consequenceon healthcare supply administration. Substantial amount ofevidence suggest that sun light is essential to burns healing andcould be exceptionally beneficial for burned patients andworkforce in healthcare building. Satisfactory UV sunlight isfundamental for a calculated amount of burn to heal; this delicaterather complex matrix is achieved by applying patternclassification for the first time on the space syntax map of the floorplan and Browder chart of the burned patient. On the basis of thedata determined from this specific healthcare learning technique,nurse can decide the location of the patient on the floor plan, hencepatient safety first is the priority in the routine tasks by staff inhealthcare settings. Whereas insufficient UV light and vitamin Dcan retard healing process, hence this experiment focuses onmachine learning design in which pattern recognition andtechnology supports patient safety as our primary goal. In thisexperiment we lowered the adverse events from 2012- 2013, andnearly missed errors and prevented medical deaths up to 50%lower, as compared to the data of 2005- 2012 before this techniquewas incorporated.In this research paper, three distinctive phases of clinicalsituations are considered—primarily: admission, secondly: acute,and tertiary: post-treatment according to the burn pattern andhealing rate—and be validated by capable AI- origin forecastingtechniques to hypothesis placement prediction models for eachclinical stage with varying percentage of burn i.e. superficialwound, partial thickness or full thickness deep burn. Conclusivelywe proved that the depth of burn is directly proportionate to thedepth of patient’s placement in terms of window distance. Ourfindings support the hypothesis that the windowed wall is mosthealing wall, here fundamental suggestion is support vectormachines: which is most advantageous hyper plane for linearlydivisible patterns for the burns depth as well as the depth map isused.

Probing the Dynamic Self-Assembly Behaviour of Photoswitchable Wormlike Micelles in Real Time

2018 ◽  
Author(s):  
Elaine A. Kelly ◽  
Judith E. Houston ◽  
Rachel Evans
Keyword(s):  
Real Time ◽  
Absorption Spectroscopy ◽  
Self Assembly ◽  
Uv Light ◽  
Wormlike Micelles ◽  
Tetraethylene Glycol ◽  
Light Illumination ◽  
First Time ◽  
Dependent Processes

Understanding the dynamic self-assembly behaviour of azobenzene photosurfactants (AzoPS) is crucial to advance their use in controlled release applications such as<i></i>drug delivery and micellar catalysis. Currently, their behaviour in the equilibrium <i>cis-</i>and <i>trans</i>-photostationary states is more widely understood than during the photoisomerisation process itself. Here, we investigate the time-dependent self-assembly of the different photoisomers of a model neutral AzoPS, <a>tetraethylene glycol mono(4′,4-octyloxy,octyl-azobenzene) </a>(C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>) using small-angle neutron scattering (SANS). We show that the incorporation of <i>in-situ</i>UV-Vis absorption spectroscopy with SANS allows the scattering profile, and hence micelle shape, to be correlated with the extent of photoisomerisation in real-time. It was observed that C<sub>8</sub>AzoOC<sub>8</sub>E<sub>4</sub>could switch between wormlike micelles (<i>trans</i>native state) and fractal aggregates (under UV light), with changes in the self-assembled structure arising concurrently with changes in the absorption spectrum. Wormlike micelles could be recovered within 60 seconds of blue light illumination. To the best of our knowledge, this is the first time the degree of AzoPS photoisomerisation has been tracked <i>in</i><i>-situ</i>through combined UV-Vis absorption spectroscopy-SANS measurements. This technique could be widely used to gain mechanistic and kinetic insights into light-dependent processes that are reliant on self-assembly.

scholarly journals Photocatalytic Reduction of CO2 to Methanol Using a Copper-Zirconia Imidazolate Framework

Catalysts ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 346
Author(s):  
Sonam Goyal ◽  
Maizatul Shima Shaharun ◽  
Ganaga Suriya Jayabal ◽  
Chong Fai Kait ◽  
Bawadi Abdullah ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Catalyst Support ◽  
Oxidation Potential ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
X Ray ◽  
Molar Ratios ◽  
Optimum Parameters ◽  
Reduction Of Co2 ◽  
Enhanced Yield

A set of novel photocatalysts, i.e., copper-zirconia imidazolate (CuZrIm) frameworks, were synthesized using different zirconia molar ratios (i.e., 0.5, 1, and 1.5 mmol). The photoreduction process of CO2 to methanol in a continuous-flow stirred photoreactor at pressure and temperature of 1 atm and 25 °C, respectively, was studied. The physicochemical properties of the synthesized catalysts were studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and photoluminescence (PL) spectroscopy. The highest methanol activity of 818.59 µmol/L.g was recorded when the CuZrIm1 catalyst with Cu/Zr/Im/NH4OH molar ratio of 2:1:4:2 (mmol/mmol/mmol/M) was employed. The enhanced yield is attributed to the presence of Cu2+ oxidation state and the uniformly dispersed active metals. The response surface methodology (RSM) was used to optimize the reaction parameters. The predicted results agreed well with the experimental ones with the correlation coefficient (R2) of 0.99. The optimization results showed that the highest methanol activity of 1054 µmol/L.g was recorded when the optimum parameters were employed, i.e., stirring rate (540 rpm), intensity of light (275 W/m2) and photocatalyst loading (1.3 g/L). The redox potential value for the CuZrIm1 shows that the reduction potential is −1.70 V and the oxidation potential is +1.28 V for the photoreduction of CO2 to methanol. The current work has established the potential utilization of the imidazolate framework as catalyst support for the photoreduction of CO2 to methanol.

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