In-Situ XPS Study of the Aluminum Poly(p-Phenylenevinylene) Interface

1995 ◽  
Vol 385 ◽  
Author(s):  
K. Konstadinidis ◽  
F. Papadimitrakopoulos ◽  
M. Galvin ◽  
R. Opila
Keyword(s):  
Valence Band ◽  
Oxygen Content ◽  
Photoelectron Spectroscopy ◽  
Surface Oxygen ◽  
Band Bending ◽  
X Ray ◽  
In Situ Xps ◽  
Synthetic Routes ◽  
Xps Study

ABSTRACTThe chemical and electronic properties of aluminum/poly(p-phenylenevinylene) (PPV) interfaces were studied in situ using x-ray photoelectron spectroscopy (XPS). It was observed that the aluminum atoms react with the oxygen-containing groups present as impurities on the surface of PPV to form Al-O-C linkages. The Al atoms also interact with the wrsystem of the polymer as indicated by changes in the valence band. Contrary to to recent suggestions (Ettedgui et al.) the relation between surface oxygen content and band bending is not straightforward, as shown by deposition on PPV surfaces prepared by two different synthetic routes.

scholarly journals in Situ X-ray Photoelectron Spectroscopic and Electrochemical Studies of the Bromide Anions Dissolved in 1-Ethyl-3-Methyl Imidazolium Tetrafluoroborate

Nanomaterials ◽  
2019 ◽  
Vol 9 (2) ◽  
pp. 304 ◽  
Author(s):  
Jaanus Kruusma ◽  
Arvo Tõnisoo ◽  
Rainer Pärna ◽  
Ergo Nõmmiste ◽  
Enn Lust
Keyword(s):  
Photoelectron Spectroscopy ◽  
Mesoporous Carbon ◽  
Residual Water ◽  
Carbon Electrode ◽  
Xps Spectra ◽  
X Ray ◽  
In Situ Xps ◽  
Vacuum Interface ◽  
Photoelectron Peak

Influence of electrode potential on the electrochemical behavior of a 1-ethyl-3-methylimidazolium tetrafluoroborate (EMImBF4) solution containing 5 wt % 1-ethyl-3-methylimidazolium bromide (EMImBr) has been investigated using electrochemical and synchrotron-initiated high-resolution in situ X-ray photoelectron spectroscopy (XPS) methods. Observation of the Br 3d5/2 in situ XPS signal, collected in a 5 wt % EMImBr solution at an EMImBF4–vacuum interface, enabled the detection of the start of the electrooxidation process of the Br- anion to Br3- anion and thereafter to the Br2 at the micro-mesoporous carbon electrode, polarized continuously at the high fixed positive potentials. A new photoelectron peak, corresponding to B–O bond formation in the B 1s in situ XPS spectra at E ≤ –1.17 V, parallel to the start of the electroreduction of the residual water at the micro-mesoporous carbon electrode, was observed and is discussed. The electroreduction of the residual water caused a reduction in the absolute value of binding energy vs. potential plot slope twice to ca. dBE dE-1 = –0.5 eV V-1 at E ≤ –1.17 V for C 1s, N 1s, B 1s, F 1s, and Br 3d5/2 photoelectrons.

Titanium Deposition on Polymer Surfaces: An Xps Study

1993 ◽  
Vol 304 ◽  
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.

Influence of band bending and polarization on the valence band offset measured by x-ray photoelectron spectroscopy

2010 ◽  
Vol 107 (10) ◽  
pp. 104510 ◽  
Author(s):  
Xiaoqing Xu ◽  
Xianglin Liu ◽  
Yan Guo ◽  
Jun Wang ◽  
Huaping Song ◽  
...  
Keyword(s):  
Valence Band ◽  
Photoelectron Spectroscopy ◽  
Band Offset ◽  
Valence Band Offset ◽  
Band Bending ◽  
X Ray

scholarly journals In situ XPS investigation of the X-ray-triggered decomposition of perovskites in ultrahigh vacuum condition

2021 ◽  
Vol 5 (1) ◽  
Author(s):  
Wei-Chun Lin ◽  
Wei-Chun Lo ◽  
Jun-Xian Li ◽  
Yi-Kai Wang ◽  
Jui-Fu Tang ◽  
...  
Keyword(s):  
Environmental Factors ◽  
Photoelectron Spectroscopy ◽  
Perovskite Structure ◽  
Uv Light ◽  
Ultrahigh Vacuum ◽  
Vacuum System ◽  
State Change ◽  
X Ray ◽  
In Situ Xps

AbstractX-ray photoelectron spectroscopy (XPS) has been used to investigate the composition of perovskite films upon exposure to different environmental factors, such as moisture, heat, and UV light. However, few research studies have determined that the X-ray itself could cause damage to the perovskite crystals. In this study, the X-ray-induced degradation of CH3NH3PbI3 perovskite films was investigated via XPS within an in situ ultrahigh vacuum system. It is demonstrated that fresh methylammonium lead iodine contains Pb2+ without the initial existence of Pb0. The Pb0 signal was discovered after a few hours of soft X-ray exposure, which indicates that the CH3NH3PbI3 perovskite structure undergoes a decomposition process to form metallic Pb. In addition, the nitrogen content was found to be significantly decreasing in the first hour of X-ray exposure. The discovery of the X-ray-induced chemical state change and the volatile methylamine of perovskite crystals could be further applied as an indicator for the field of X-ray sensors or detectors.

scholarly journals In situ monitoring of the influence of water on DNA radiation damage by near-ambient pressure X-ray photoelectron spectroscopy

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Marc Benjamin Hahn ◽  
Paul M. Dietrich ◽  
Jörg Radnik
Keyword(s):  
Dna Damage ◽  
Radiation Damage ◽  
Photoelectron Spectroscopy ◽  
Ambient Pressure ◽  
In Situ Monitoring ◽  
Strong Increase ◽  
Oh Radicals ◽  
Strand Breaks ◽  
X Ray

AbstractIonizing radiation damage to DNA plays a fundamental role in cancer therapy. X-ray photoelectron-spectroscopy (XPS) allows simultaneous irradiation and damage monitoring. Although water radiolysis is essential for radiation damage, all previous XPS studies were performed in vacuum. Here we present near-ambient-pressure XPS experiments to directly measure DNA damage under water atmosphere. They permit in-situ monitoring of the effects of radicals on fully hydrated double-stranded DNA. The results allow us to distinguish direct damage, by photons and secondary low-energy electrons (LEE), from damage by hydroxyl radicals or hydration induced modifications of damage pathways. The exposure of dry DNA to x-rays leads to strand-breaks at the sugar-phosphate backbone, while deoxyribose and nucleobases are less affected. In contrast, a strong increase of DNA damage is observed in water, where OH-radicals are produced. In consequence, base damage and base release become predominant, even though the number of strand-breaks increases further.

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