Photoreduction of Hexavalent Chromium during X‐Ray Photoelectron Spectroscopy Analysis of Electrochemical and Thermal Films

AbstractPassivation of nanoscale zerovalent iron hinders its efficiency in water treatment, and loading another catalytic metal has been found to improve the efficiency significantly. In this study, Cu/Fe bimetallic nanoparticles were prepared by liquid-phase chemical reduction for removal of hexavalent chromium (Cr(VI)) from wastewater. Synthesized bimetallic nanoparticles were characterized by transmission electron microscopy, Brunauer–Emmet–Teller isotherm, and X-ray diffraction. The results showed that Cu loading can significantly enhance the removal efficiency of Cr(VI) by 29.3% to 84.0%, and the optimal Cu loading rate was 3% (wt%). The removal efficiency decreased with increasing initial pH and Cr(VI) concentration. The removal of Cr(VI) was better fitted by pseudo-second-order model than pseudo-first-order model. Thermodynamic analysis revealed that the Cr(VI) removal was spontaneous and endothermic, and the increase of reaction temperature facilitated the process. X-ray photoelectron spectroscopy (XPS) analysis indicated that Cr(VI) was completely reduced to Cr(III) and precipitated on the particle surface as hydroxylated Cr(OH)3 and CrxFe1−x(OH)3 coprecipitation. Our work could be beneficial for the application of iron-based nanomaterials in remediation of wastewater.

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X‐ray photoelectron spectroscopy analysis of photostimulated chemical vapor deposition hydrogenated amorphous silicon/amorphous aluminum oxide

Applied Physics Letters ◽

10.1063/1.107407 ◽

1992 ◽

Vol 60 (10) ◽

pp. 1208-1210 ◽

Cited By ~ 1

Author(s):

K. Uwasawa ◽

F. Ishihara ◽

S. Matsumoto

Keyword(s):

Chemical Vapor Deposition ◽

Aluminum Oxide ◽

Amorphous Silicon ◽

Vapor Deposition ◽

Photoelectron Spectroscopy ◽

Hydrogenated Amorphous Silicon ◽

Chemical Vapor ◽

Spectroscopy Analysis ◽

X Ray ◽

Hydrogenated Amorphous

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X-ray photoelectron spectroscopy and positron annihilation spectroscopy analysis of surfactant affected FePt spintronic films

Applied Surface Science ◽

10.1016/j.apsusc.2014.04.190 ◽

2014 ◽

Vol 308 ◽

pp. 408-413 ◽

Cited By ~ 1

Author(s):

Chun Feng ◽

Xujing Li ◽

Fen Liu ◽

Qiang Wang ◽

Meiyin Yang ◽

...

Keyword(s):

Positron Annihilation ◽

Photoelectron Spectroscopy ◽

Positron Annihilation Spectroscopy ◽

Spectroscopy Analysis ◽

X Ray

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SiO2 films as heat resistant layers for protection of expandable polystyrene foam from flame torch–induced heat

Journal of Thermoplastic Composite Materials ◽

10.1177/0892705717718238 ◽

2017 ◽

Vol 31 (5) ◽

pp. 657-667 ◽

Cited By ~ 1

Author(s):

S Varnagiris ◽

S Tuckute ◽

M Lelis ◽

D Milcius

Keyword(s):

Heat Resistance ◽

Photoelectron Spectroscopy ◽

Silicon Oxide ◽

Plasma Generator ◽

Expanded Polystyrene ◽

Spectroscopy Analysis ◽

X Ray ◽

Heat Resistant ◽

Pulsed Dc ◽

Gas Atmosphere

Currently, polymeric insulation materials are widely used for energy saving in buildings. Despite of all benefits, these materials are generally sensitive to heat and highly flammable. This work discusses possibility to improve heat resistance of expanded polystyrene (EPS) foam using thin silicon dioxide (SiO2) films deposited by magnetron sputtering technique. In order to increase surface energy and adherence of SiO2 thin films to substrate EPS was plasma pretreated before films’ depositions using pulsed DC plasma generator for 40 s in argon gas. SiO2 formation was done in reactive argon and oxygen gas atmosphere. Laboratory made equipment was used for flame torch–induced heat resistance experiments. Results showed that silicon oxide films remains stable during heat resistance experiments up to 5 s and fully protects polystyrene (PS) substrate. Films are relatively stable for 30 s and 60 s and partially protect PS from melting and ignition. Scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray photoelectron spectroscopy analysis confirmed that SiO2 layer, which is distributed uniformly on the EPS surface, could work as a good heat resistant material.

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Effect of Sodium Metabisulfite on Selective Flotation of Chalcopyrite and Molybdenite

Minerals ◽

10.3390/min11121377 ◽

2021 ◽

Vol 11 (12) ◽

pp. 1377

Author(s):

Yuki Semoto ◽

Gde Pandhe Wisnu Suyantara ◽

Hajime Miki ◽

Keiko Sasaki ◽

Tsuyoshi Hirajima ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Separation Efficiency ◽

Diesel Oil ◽

Sodium Metabisulfite ◽

Depressing Effect ◽

Spectroscopy Analysis ◽

X Ray ◽

Selective Flotation

Sodium metabisulfite (MBS) was used in this study for selective flotation of chalcopyrite and molybdenite. Microflotation tests of single and mixed minerals were performed to assess the floatability of chalcopyrite and molybdenite. The results of microflotation of single minerals showed that MBS treatment significantly depressed the floatability of chalcopyrite and slightly reduced the floatability of molybdenite. The results of microflotation of mixed minerals demonstrated that the MBS treatment could be used as a selective chalcopyrite depressant in the selective flotation of chalcopyrite and molybdenite. Furthermore, the addition of diesel oil or kerosene could significantly improve the separation efficiency of selective flotation of chalcopyrite and molybdenite using MBS treatment. A mechanism based on X-ray photoelectron spectroscopy analysis results is proposed in this study to explain the selective depressing effect of MBS on the flotation of chalcopyrite and molybdenite.

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