X-ray Photoelectron Spectroscopy(XPS) Study of Fracture Mechanism in Sintered Si3N4.

ABSTRACTThe nitridation process of a polytitanocarbosilane, leading to the formation of a Si-Ti-N-O ceramics, has been investigated mainly by means of X-ray photoelectron spectroscopy (XPS). Ti2p spectra collected on samples fired at various stages of the transformation process clearly shown that Ti-N bonds of TiOxNy mixed units start to form at 500 °C. By increasing the firing temperature, the Ti2p peak shifts toward values typical of titanium nitride ceramics, so indicating the progressive nitrogen enrichment of the mixed units up to the formation of a TiN phase.

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XPS STUDY OF DOPING MECHANISM IN HEAVILY DOPED PbWO4:M3+(M = La, Nd, Gd) CRYSTALS

Surface Review and Letters ◽

10.1142/s0218625x07010007 ◽

2007 ◽

Vol 14 (04) ◽

pp. 725-728

Author(s):

XIQI FENG ◽

WEIFENG LI ◽

WENLIANG ZHU

Keyword(s):

Photoelectron Spectroscopy ◽

Rare Earth Ions ◽

High Concentration ◽

Lead Tungstate ◽

X Ray ◽

Optoelectronic Application ◽

Trivalent Rare Earth ◽

Heavily Doped ◽

Doping Mechanism ◽

Xps Study

Lead tungstate ( PbWO 4) (PWO) crystals doped with high concentration trivalent rare earth ions have demonstrated to be a promising Cherenkov radiator material and also a potential material for optoelectronic application. In this paper, the doping mechanisms of the trivalent ions ( La 3+, Nd 3+, and Gd 3+) in the PWO host were studied using X-ray photoelectron spectroscopy (XPS), and the results were consistent with those of computer simulation. It was found that when heavily doped, La 3+ may substitute for the W sites as well as the Pb sites for self-compensation by forming La dimers or small aggregates. However, the doping mechanism of heavily doped PWO: Nd 3+ and PWO: Gd 3+ might be different from that of heavily doped PWO: La 3+ crystals.

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XPS Study of a New Heterogeneous Ruthenium Catalyst Precursor

Applied Spectroscopy ◽

10.1366/0003702971939875 ◽

1997 ◽

Vol 51 (12) ◽

pp. 1807-1813 ◽

Cited By ~ 2

Author(s):

P. Smet ◽

F. Verpoort ◽

G. De Doncker ◽

A. R. Bossuyt ◽

L. Fiermans ◽

...

Keyword(s):

Thin Layer ◽

Photoelectron Spectroscopy ◽

Surface Reaction ◽

Silica Surface ◽

Silicon Single Crystal ◽

Catalyst Precursor ◽

X Ray ◽

Different Types ◽

Xps Study

The catalyst precursor has been synthesized by modifying the silica surface with ClPPh2 followed by a surface reaction with RuCl3. Supports consisting of a thin layer of SiO2 on a silicon single crystal have been used. Characterization of the different stages in the reaction procedure has been performed by a combination of conventional and angle-resolved X-ray photoelectron spectroscopy (XPS) using RuCl3/P(C6H5)2/SiO2/Si(100) model precursors. Different types of ruthenium centra have been identified.

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XPS STUDY OF INTERACTION OF TITANIUM SPECIES WITH DIFFERENT INTERNAL ELECTRON DONORS ON Z–N CATALYSTS

Surface Review and Letters ◽

10.1142/s0218625x07010482 ◽

2007 ◽

Vol 14 (05) ◽

pp. 951-955 ◽

Cited By ~ 5

Author(s):

XI ZHAO ◽

YING ZHANG ◽

YANG SONG ◽

GANG WEI

Keyword(s):

Electron Density ◽

Photoelectron Spectroscopy ◽

Catalyst Activity ◽

Electron Donors ◽

X Ray ◽

Internal Donor ◽

Species Effect ◽

Chemical States ◽

Internal Electron ◽

Xps Study

TiCl 4/ MgCl 2, TiCl 4/ MgCl 2/donor catalysts and TiCl 4/donor complexes were prepared in this experiment; the donors are EB, DNBP, DBPG, DBW, PPDE, and BMMF respectively. Chemical states of Ti on the surface of MgCl 2-supported Z – N catalysts were analyzed with X-ray photoelectron spectroscopy (XPS). The interaction among components of a catalyst is characterized, and the function of internal donor in the catalyst was demonstrated according to the change of binding energy of Ti 2 p 3/2. We may conclude from the experiment that the kind of internal donors influence the electron density around titanium, and further the electron density around active titanium species effect catalyst activity to some extent. It was also noted that the interaction between internal donors and titanium is weakened remarkably by moisture and oxygen in ambient.

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Titanium Deposition on Polymer Surfaces: An Xps Study

MRS Proceedings ◽

10.1557/proc-304-83 ◽

1993 ◽

Vol 304 ◽

Cited By ~ 1

Author(s):

K. Konstadinidis ◽

R. L. Opila ◽

J. A. Taylor ◽

A. C. Miller

Keyword(s):

Titanium Carbide ◽

Photoelectron Spectroscopy ◽

Polymer Surfaces ◽

Chemical Interactions ◽

X Ray ◽

Stable Oxide ◽

Xps Study ◽

Aging In Air

AbstractWe have used X-ray Photoelectron Spectroscopy to study the chemical interactions at the interface formed during in situ deposition of Ti atoms on triazine, polyimide (PMDAODA), and polystyrene surfaces. For deposition on thin triazine films (∼ 100Å) we observe that titanium carbide is the dominant product, while oxides and nitrides are formed as well. Aging in air causes the carbide and nitride to convert to the more thermodynamically stable oxide. Titanium carbide is also the primary species at the Ti/polyimide and Ti/polystyrene interface. In all cases the reaction of Ti atoms with different sites in the polymer is nonselective.

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X-ray photoelectron spectroscopy (XPS) study of Heusler alloy (Co2FeAl) interfaced with semiconductor (n-Si) structure

Materials Science-Poland ◽

10.2478/msp-2019-0001 ◽

2019 ◽

Vol 37 (1) ◽

pp. 116-121

Author(s):

Arvind Kumar ◽

P.C. Srivastava

Keyword(s):

Electronic Structure ◽

Transport Properties ◽

Photoelectron Spectroscopy ◽

Heusler Alloy ◽

Crucial Role ◽

Chemical State ◽

X Ray ◽

Si Substrates ◽

Magnetic Heterostructures ◽

Xps Study

AbstractLayered magnetic heterostructures are very promising candidates in spintronics in which the influences of interfaces, surfaces and defects play a crucial role. X-ray photoelectron spectroscopy (XPS) study has been performed for studying in detail the chemical state and electronic structure of Co2FeAl (CFA) Heusler alloy interfaced with Si substrates. XPS survey scan spectra have clearly shown the presence of Fe, Co and Al signal along with the signal due to Si. The presence of Co, Fe and Al signal confirms the formation of CFA alloy phase. Our XPS results support our previous study [1] on CFA/Si structure in determining the magnetic and transport properties across the interface.

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The XPS study of physical and chemical forms of neptunium group on the surface of minerals

Nuclear Technology and Radiation Protection ◽

10.2298/ntrp1001001t ◽

2010 ◽

Vol 25 (1) ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Anton Teterin ◽

Alevtina Mikhailina ◽

Konstantin Maslakov ◽

Elena Zaharova ◽

Yury Teterin

Keyword(s):

Photoelectron Spectroscopy ◽

Ionic Composition ◽

Liquid Extraction ◽

Sorption Behavior ◽

Chemical Forms ◽

X Ray ◽

Oxygen Ions ◽

Liquid Liquid Extraction ◽

Xps Study ◽

Physical And Chemical

The sorption behavior and the physical and chemical forms of neptunium on the surface of minerals of the two chlorate samples, biotite and kaolin, with different contents of Fe(II) was studied. The liquid-liquid extraction and the X-ray photoelectron spectroscopy were employed to identify the valence forms of neptunium. On the basis of the obtained data the quantitative elemental composition of the surface of the studied minerals, as well as the ionic composition of the formed neptunium complexes was determined. It was shown that the Np(IV) and Np(VI) containing compounds did not form, while the complexes Np(V)O+ -hydroxyl did form on the surface. The oxygen ions bonded with iron and oxygen belonging to water and/or of carboxyl were suggested to be present in the equatorial plane of the neptunyl group NpO+.

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XPS Study of Polyimide H-Film After Heat Treatment and Laser Processing

MRS Proceedings ◽

10.1557/proc-154-363 ◽

1989 ◽

Vol 154 ◽

Cited By ~ 2

Author(s):

P.V. Nagarkar ◽

E.K. Sichela ◽

G.L. Doll

Keyword(s):

Heat Treatment ◽

Electrical Resistivity ◽

Photoelectron Spectroscopy ◽

Laser Processing ◽

Surface Composition ◽

Carbonyl Groups ◽

X Ray ◽

Heat Treated ◽

Rapid Changes ◽

Xps Study

AbstractAn x-ray photoelectron spectroscopy (XPS) study of laser treated and heat treated Kapton®indicates that both the treatments result in depleting the carbonyl groups from the sample and leave behind a conducting residue that still contains significant amounts of oxygen and nitrogen. The rapid changes in surface composition coincide with a substantial decrease in the electrical resistivity of the polyimide samples.

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XPS Study of Plasma Modified PVDF-TrFE Films Surface

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1134.12 ◽

2015 ◽

Vol 1134 ◽

pp. 12-15

Author(s):

Muhamad Naiman Sarip ◽

Rozana Mohd Dahan ◽

Yap Seong Ling ◽

Mohamad Hafiz Mohd Wahid ◽

Adillah Nurashikin Arshad ◽

...

Keyword(s):

Exposure Time ◽

Photoelectron Spectroscopy ◽

Argon Plasma ◽

Film Surface ◽

Atomic Percent ◽

Plasma Modification ◽

X Ray ◽

Main Emphasis ◽

Xps Study ◽

The Impact

The impact of surface plasma modification on PVDF-TrFE film with different exposure time was investigated using X-ray photoelectron spectroscopy (XPS). The main emphasis of this study was to optimize the exposure time of argon plasma on the surface of PVDF-TrFE films The surface of spin coated PVDF-TrFE film was modified with argon plasma at exposure time of 1, 3, 5, 7 and 9 min/s. Prior to modification, only small amount of atomic percent (1.92 %) of O1s peak was observed at 540.8 eV, but upon modification, the atomic percent for O1s peak was found to increase to 8.8 %. Meanwhile, the atomic percent for F1s peak observed at 695.3 eV was found to decrease from 70.6 % to 61.2 %. This phenomenon is an indication that plasma modified PVDF-TrFE films were readily oxidized. Importantly, most of the fluorine elements were removed from the modified PVDF-TrFE film surface, which rendered the film favourable for adhesion with other material for coating aplications.

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XPS Study of Poisoning Mechanism of O2 on LaNi4.7Al0.3 Oxygen

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.519.96 ◽

2012 ◽

Vol 519 ◽

pp. 96-99

Author(s):

Ge Sang ◽

Ming Jing Tu ◽

Sheng Wu ◽

Xiao Guo Fu ◽

Qua Nan Li ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

X Ray ◽

Xps Study ◽

Poisonous Effect

In this paper, LaNi4.7Al0.3 alloy samples were obtained via melting in middle frequency influence fire .In addition, The alloy pellets were milled for absorbing and desorbing Hydrogen ability study, The P-V-T measurement provided us with poisonous effect on the oxidation of LaNi4.7Al0.3.To understand the poisoning mechanism of O2 on LaNi4.7Al0.3, the X-ray photoelectron spectroscopy (XPS) was introduced to analyzed the process of poisoning of LaNi4.7Al0.3 alloy, Which revealed the changes of the valence of the elements of the alloy LaNi4.7Al0.3 poisoned by O2.

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