Assigning Oxidation States to Organic Compounds via Predictions from X-ray Photoelectron Spectroscopy: A Discussion of Approaches and Recommended Improvements

2013 ◽  
Vol 91 (2) ◽  
pp. 232-238 ◽  
Author(s):  
Vipul Gupta ◽  
Hasitha Ganegoda ◽  
Mark H. Engelhard ◽  
Jeff Terry ◽  
Matthew R. Linford
Keyword(s):  
Organic Compounds ◽  
Photoelectron Spectroscopy ◽  
Oxidation States ◽  
X Ray

scholarly journals Photocatalytic CO2 Reduction and Electrocatalytic H2 Evolution over Pt(0,II,IV)-Loaded Oxidized Ti Sheets

Nanomaterials ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1909
Author(s):  
Ju Hyun Yang ◽  
So Jeong Park ◽  
Choong Kyun Rhee ◽  
Youngku Sohn
Keyword(s):  
Hydrogen Evolution ◽  
Photoelectron Spectroscopy ◽  
Co2 Reduction ◽  
Oxidation States ◽  
X Ray ◽  
Catalytic Activities ◽  
Before And After ◽  
Reduction Methods ◽  
Chemical States ◽  
Sputter Deposited

Energy recycling and production using abundant atmospheric CO2 and H2O have increasingly attracted attention for solving energy and environmental problems. Herein, Pt-loaded Ti sheets were prepared by sputter-deposition and Pt4+-reduction methods, and their catalytic activities on both photocatalytic CO2 reduction and electrochemical hydrogen evolution were fully demonstrated. The surface chemical states were completely examined by X-ray photoelectron spectroscopy before and after CO2 reduction. Gas chromatography confirmed that CO, CH4, and CH3OH were commonly produced as CO2 reduction products with total yields up to 87.3, 26.9, and 88.0 μmol/mol, respectively for 700 °C-annealed Ti under UVC irradiation for 13 h. Pt-loading commonly negated the CO2 reduction yields, but CH4 selectivity was increased. Electrochemical hydrogen evolution reaction (HER) activity showed the highest activity for sputter-deposited Pt on 400 °C-annealed Ti with a HER current density of 10.5 mA/cm2 at −0.5 V (vs. Ag/AgCl). The activities of CO2 reduction and HER were found to be significantly dependent on both the nature of Ti support and the oxidation states (0,II,IV) of overlayer Pt. The present result could provide valuable information for designing efficient Pt/Ti-based CO2 recycle photocatalysts and electrochemical hydrogen production catalysts.

An X-Ray Photoelectron Spectroscopic Study of Copper Chromite Catalysts

1979 ◽  
Vol 33 (4) ◽  
pp. 380-384 ◽  
Author(s):  
J. A. Schreifels ◽  
A. Rodero ◽  
W. E. Swartz
Keyword(s):  
Spectroscopic Study ◽  
Calcination Temperature ◽  
Photoelectron Spectroscopy ◽  
Copper Chromite ◽  
Oxidation States ◽  
Surface Species ◽  
Catalytic Surface ◽  
X Ray

A series of copper chromite catalysts have been studied by x-ray photoelectron spectroscopy. The data indicate that in the as-received form the copper is present as a mixture of Cu(OH)2 and CuO. After calcination at 500 °C only CuO is present. The chromium is present as Cr+3 and Cr+4 when no promoter is added. When a BaO promoter is added, the Cr+6 is stabilized. Calcination at 500°C for varying periods of time alter the relative amounts of Cr+3 and Cr+6 on the catalytic surface. In addition, the relative amounts of the various oxidation states are a function of calcination temperature. At a calcination temperature of 240°C a Cr+5 surface species is reproducibly observed in one of the catalysts.

Single-layer MoS2formation by sulfidation of molybdenum oxides in different oxidation states on Au(111)

2017 ◽  
Vol 19 (21) ◽  
pp. 14020-14029 ◽  
Author(s):  
Norberto Salazar ◽  
Igor Beinik ◽  
Jeppe V. Lauritsen
Keyword(s):  
Scanning Tunneling Microscopy ◽  
Photoelectron Spectroscopy ◽  
Single Layer ◽  
Oxidation States ◽  
Scanning Tunneling ◽  
Molybdenum Oxides ◽  
Tunneling Microscopy ◽  
X Ray

The sulfidation pathway from MoO3to MoS2on Au(111) revealed by a combination of Scanning Tunneling Microscopy and X-Ray Photoelectron Spectroscopy.

Characterization of europium implanted LiNbO3

1993 ◽  
Vol 8 (10) ◽  
pp. 2679-2685 ◽  
Author(s):  
P. Moretti ◽  
B. Canut ◽  
S.M.M. Ramos ◽  
R. Brenier ◽  
P. Thévenard ◽  
...  
Keyword(s):  
Single Crystals ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Rutherford Backscattering ◽  
Oxidation States ◽  
Xps Spectra ◽  
X Ray ◽  
Partial Recrystallization ◽  
Lower Charge

LiNbO3 single crystals were implanted at room temperature with Eu+ ions at 70 keV with fluence ranging from 0.5 to 5 × 1016 ions · cm−2. The damage in the implanted layer has been investigated by Channeling Rutherford Backscattering (RBS-C), and the oxidation states of the cations have been determined by x-ray photoelectron spectroscopy (XPS). Following implantation, a fully amorphized layer of 60 nm is generated, even for the lowest fluence employed. Subsequent annealing in air, in the range 800–1250 K, was applied to restore tentatively the crystallinity and promote the substitutional incorporation of Eu in the crystal. Only a partial recrystallization of the damaged layer was observed. For as-implanted samples, XPS spectra clearly reveal europium in Eu2+ and Eu3+ states, and the Nb5+ ions are driven to lower charge states.

OXIDATION STATES OF IRON IN BAHAMIAN POTTERY BY X-RAY PHOTOELECTRON SPECTROSCOPY

Archaeometry ◽  
1990 ◽  
Vol 32 (1) ◽  
pp. 47-54 ◽  
Author(s):  
J. B. LAMBERT ◽  
L. XUE ◽  
J. M. WEYDERT ◽  
J. H. WINTER
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxidation States ◽  
X Ray

scholarly journals Effect of reaction parameters on WOx nanostructures by the solvothermal process

2021 ◽  
Vol 4 (3) ◽  
pp. 234-244
Author(s):  
Amelia Olivas Sarabia ◽  
Marlene N Cardoza-Contreras ◽  
Gonzalo Lastra Medina ◽  
Marcos Alan Cota Leal ◽  
Selene Sepúlveda Guzmán
Keyword(s):  
Acetic Acid ◽  
Reaction Time ◽  
Photoelectron Spectroscopy ◽  
Solvothermal Method ◽  
Ultra Violet ◽  
Oxidation States ◽  
X Ray Diffraction ◽  
Reaction Parameters ◽  
X Ray ◽  
Xrd Patterns

In this work, nanowires and nanorods of WOx have been synthesized by the solvothermal method. The effect of reaction time and acetic acid as solvent were studied. X-ray diffraction (XRD) patterns showed the monoclinic WO2.72, WO2.79, and orthorhombic WO3 crystalline structures. Scanning Electron Microscopy (SEM) and High-Resolution Transmission Electronic Microscopy (HRTEM) images presented nanostructures such as nanowires and nanorods at different sizes. Band gap energies were supplied by Ultra Violet visible (UV-vis) absorption spectra. The Photoluminescence (PL) spectra exhibited three emission peaks in the blue zone at 440, 460, and 484 nm. X-ray Photoelectron Spectroscopy (XPS) was used to calculate W6+, W5+, and W4+ oxidation states. The results showed that increasing the reaction time from 10 h to 24 h affected the crystalline structure from monoclinic to orthorhombic. Moreover, with the addition of acetic acid as solvent, the crystal structure is not affected but stabilizes the monoclinic phase in the course of time.

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