Electronic states of core levels and valence bands for KxC60 studied by X-ray photoelectron spectroscopy

The price and scarcity of platinum has driven up the demand for non-precious metal catalysts such as Fe-N-C. In this study, the effects of phosphoric acid (PA) activation and phosphorus doping were investigated using Fe-N-C catalysts prepared using SBA-15 as a sacrificial template. The physical and structural changes caused by the addition of PA were analyzed by nitrogen adsorption/desorption and X-ray diffraction. Analysis of the electronic states of Fe, N, and P were conducted by X-ray photoelectron spectroscopy. The amount and size of micropores varied depending on the PA content, with changes in pore structure observed using 0.066 g of PA. The electronic states of Fe and N did not change significantly after treatment with PA, and P was mainly found in states bonded to oxygen or carbon. When 0.135 g of PA was introduced per 1 g of silica, a catalytic activity which was increased slightly by 10 mV at −3 mA/cm2 was observed. A change in Fe-N-C stability was also observed through the introduction of PA.

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Electronic structure of Ni and Pd alloys. I. X-ray photoelectron spectroscopy of the valence bands

Physical Review B ◽

10.1103/physrevb.27.2145 ◽

1983 ◽

Vol 27 (4) ◽

pp. 2145-2178 ◽

Cited By ~ 292

Author(s):

John C. Fuggle ◽

F. Ulrich Hillebrecht ◽

R. Zeller ◽

Zygmunt Zołnierek ◽

Peter A. Bennett ◽

...

Keyword(s):

Electronic Structure ◽

Photoelectron Spectroscopy ◽

X Ray ◽

Valence Bands

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VUV and Soft X-ray Spectroscopy of Actinides

MRS Proceedings ◽

10.1557/proc-802-dd2.5 ◽

2003 ◽

Vol 802 ◽

Author(s):

Clifford G. Olson ◽

John J. Joyce ◽

Tomasz Durakiewicz ◽

Elzbieta Guziewicz ◽

Martin Butterfield

Keyword(s):

Cross Section ◽

Cross Sections ◽

Spectral Characteristics ◽

Electronic States ◽

Momentum Dependence ◽

Auger Electrons ◽

X Ray ◽

Relative Cross Section ◽

Initial States ◽

Valence Bands

ABSTRACTOptical and photoelectron spectroscopies using VUV and Soft X-ray photons are powerful tools for studies of elemental and compound actinides. Large changes in the relative atomic cross sections of the 5f, 6d and sp electrons allow decomposition of the character of the valence bands using photoemission. Resonant enhancement of photoelectrons and Auger electrons at the 5d core threshold further aids the decomposition and gives a measure of elemental specificity. Angle-resolved photoemission can be used to map the momentum dependence of the electronic states. The large changes in relative cross section with photon energy yields further details when the mapping is done at equivalent points in multiple zones. Spectra for well understood rare earth materials will be presented to establish spectral characteristics for known atomic character initial states. These signatures will be applied to the case of USb to investigate f-d hybridization near the Fermi level.

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Photoelectron Angular Distributions Of Ultrathin NI/CU(001) Films

MRS Proceedings ◽

10.1557/proc-437-39 ◽

1996 ◽

Vol 437 ◽

Author(s):

G.J. Mankey ◽

K. Subramanian ◽

R.L. Stockbauer ◽

R.L. Kurtz

Keyword(s):

Photoelectron Spectroscopy ◽

Periodic Potential ◽

Electronic States ◽

Linear Dichroism ◽

Angular Distributions ◽

X Ray ◽

Photoelectron Diffraction ◽

Ellipsoidal Mirror ◽

Magnetic Linear Dichroism ◽

Photoelectron Angular Distributions

AbstractWe present measurements of the evolution with film thickness of the 3d electronic states at the Fermi energy of ultrathin Ni films. The morphology and thickness of the films is determined from x-ray photoelectron spectroscopy. x-ray photoelectron diffraction and x-ray magnetic linear dichroism using synchrotron radiation. Photoelectron angular distributions were measured using an ellipsoidal mirror analyzer. Even at submonolayer Ni coverages, the 3d electronic states exhibit bulk-like properties. This is attributed to the short screening length of electrons in metals, the localization of the 3d electrons, the similarity of the Ni and Cu ion cores, and finally the interaction with the underlying fcc periodic potential.

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The Control of Electronic States Spreading Outside the Conjugated Polymer Surface

MRS Proceedings ◽

10.1557/proc-0965-s13-02 ◽

2006 ◽

Vol 965 ◽

Author(s):

Xiao Tao Hao ◽

Takuya Hosokai ◽

Noritaka Mitsuo ◽

Satoshi Kera ◽

Kazuyuki Sakamoto ◽

...

Keyword(s):

Thin Films ◽

Photoelectron Spectroscopy ◽

Electronic Structures ◽

Conjugated Polymer ◽

Polymer Surface ◽

Electronic States ◽

Penning Ionization ◽

X Ray ◽

Molecular Ordering ◽

X Ray Absorption

ABSTRACTThe surface electronic structures of conjugated regio regular and regio random poly (3- hexylthiophene) (rr-P3HT and rra-P3HT) thin films were studied by near edge X-ray absorption fine structure spectroscopy, ultraviolet photoelectron spectroscopy and Penning ionization electron spectroscopy (PIES). The distribution of the surface electronic states was controlled on rr-P3HT and rra-P3HT thin films with different molecular ordering by varying the coating process and PIES was adopted to observe the electronic states existing outside the surface.

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New Direct Spectroscopic Method for Determination of Bias-Dependent Electronic States: Hard X-ray Photoelectron Spectroscopy Under Device Operation

Japanese Journal of Applied Physics ◽

10.7567/jjap.52.108005 ◽

2013 ◽

Vol 52 (10R) ◽

pp. 108005 ◽

Cited By ~ 3

Author(s):

Yoshiyuki Yamashita ◽

Hideki Yoshikawa ◽

Toyohiro Chikyo ◽

Keisuke Kobayashi

Keyword(s):

Photoelectron Spectroscopy ◽

Spectroscopic Method ◽

Electronic States ◽

X Ray ◽

Device Operation

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CORRELATION AMONG THE ELECTRONIC STATE IN Sn-DOPED YBCO SYSTEM

Modern Physics Letters B ◽

10.1142/s0217984991000691 ◽

1991 ◽

Vol 05 (08) ◽

pp. 581-585

Author(s):

H. ZHANG ◽

S.Q. FENG ◽

Q.R. FENG ◽

X. ZHU

Keyword(s):

Content Analysis ◽

Binding Energy ◽

Photoelectron Spectroscopy ◽

Strong Correlation ◽

Single Phase ◽

Vacuum Chamber ◽

High Vacuum ◽

Electronic States ◽

Ultra High Vacuum ◽

X Ray

We have performed an X-ray photoelectron spectroscopy investigation on single-phase samples of Sn -doped YBCO system, together with structure analysis, oxygen content analysis, and superconductivity measurements. The experiment gave evidence that there is a strong correlation between the electronic states of copper and oxygen. When the sample was heated to 600°C for 20 minutes in vacuum chamber, the oxygen escaped from the sample, the binding energy of Cu 2p was decreased, and the two indistinct components of O 1s became clear. Keeping the sample in ultra-high vacuum for 24 hours, a similar result was obtained.

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From antiferromagnetic and hidden order to Pauli paramagnetism in UM2Si2compounds with 5felectron duality

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2005701117 ◽

2020 ◽

Vol 117 (48) ◽

pp. 30220-30227 ◽

Cited By ~ 1

Author(s):

Andrea Amorese ◽

Martin Sundermann ◽

Brett Leedahl ◽

Andrea Marino ◽

Daisuke Takegami ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Degrees Of Freedom ◽

Magnetic Moments ◽

Electronic States ◽

Dual Nature ◽

X Ray ◽

X Ray Scattering ◽

Hidden Order ◽

Pauli Paramagnetism ◽

Ray Scattering

Using inelastic X-ray scattering beyond the dipole limit and hard X-ray photoelectron spectroscopy we establish the dual nature of the U5felectrons in UM2Si2(M = Pd, Ni, Ru, Fe), regardless of their degree of delocalization. We have observed that the compounds have in common a local atomic-like state that is well described by the U5f2configuration with theΓ1(1)andΓ2quasi-doublet symmetry. The amount of the U 5f3configuration, however, varies considerably across the UM2Si2series, indicating an increase of U 5f itineracy in going from M = Pd to Ni to Ru and to the Fe compound. The identified electronic states explain the formation of the very large ordered magnetic moments inUPd2Si2andUNi2Si2, the availability of orbital degrees of freedom needed for the hidden order inURu2Si2to occur, as well as the appearance of Pauli paramagnetism inUFe2Si2. A unified and systematic picture of the UM2Si2compounds may now be drawn, thereby providing suggestions for additional experiments to induce hidden order and/or superconductivity in U compounds with the tetragonal body-centeredThCr2Si2structure.

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Interface-Induced Plasmon Nonhomogeneity in Nanostructured Metal-Dielectric Planar Metamaterial

Journal of Nanomaterials ◽

10.1155/2015/876247 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

A. I. Kovalev ◽

D. L. Wainstein ◽

A. Yu. Rashkovskiy ◽

R. Gago ◽

F. Soldera ◽

...

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Electron Spectroscopy ◽

Auger Electron ◽

Electronic States ◽

Energy Losses ◽

Critical Layer Thickness ◽

Characteristic Energy ◽

X Ray ◽

Nanostructured Metal

Transformations of the electronic structure in thin silver layers in metal-dielectric (TiAlN/Ag) multilayer nanocomposite were investigated by a set of electron spectroscopy techniques. Localization of the electronic states in the valence band and reduction of electron concentration in the conduction band was observed. This led to decreasing metallic properties of silver in the thin films. A critical layer thickness of 23.5 nm associated with the development of quantum effects was determined by X-ray photoelectron spectroscopy. Scanning Auger electron microscopy of characteristic energy losses provided images of plasmon localization in the Ag layers. The nonuniformity of plasmon intensities distribution near the metal-nitride interfaces was assessed experimentally.

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