Surface Oxidation of Si (111) By High Purity Ozone and Negative Ions Produced by Rydberg Electron Transfer

1996 ◽  
Vol 446 ◽  
Author(s):  
H. Nonaka ◽  
A. Kurokawa ◽  
K. Nakamura ◽  
S. Ichimura
Keyword(s):  
Electron Transfer ◽  
High Purity ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Surface Oxidation ◽  
Negative Ions ◽  
High Flux ◽  
Initial Oxidation ◽  
X Ray ◽  
Rydberg Electron

AbstractThe sub‐initial oxidation of Si (111) surface by a high‐flux pure ozone was investigated using X‐ray photoelectron spectroscopy. In addition to the advantage of the pure ozone which can efficiently oxidize the Si surface at room temperature, the high‐flux ozone was found to further enhance the oxidation. The possibility of producing negative ions of oxidizing gases using Rydberg electron transfer was also investigated.

Photo-Chemical Changes of Aluminium Films on Silicon

1988 ◽  
Vol 119 ◽  
Author(s):  
A. J. Kellock ◽  
J. S. Williams ◽  
G. L. Nyberg ◽  
J. Liesegang
Keyword(s):  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Surface Oxidation ◽  
Rutherford Backscattering ◽  
Rutherford Backscattering Spectroscopy ◽  
Chemical Changes ◽  
X Ray ◽  
Surface And Interface ◽  
Photon Irradiation

AbstractX-ray Photoelectron Spectroscopy and Rutherford Backscattering Spectroscopy with channeling are employed to study surface and interface changes resulting from irradiation of thin Al films on Si-SiO2 substrates using < 6eV visible photons. Results indicati that surface oxidation and bonding rearrangements at the Al-SiO2-Si interface can take place at room temperature under photon bombardment. These changes are correlated with enhanced adhesion and modification of film etch properties which are also a result of photon irradiation.

The Surface Oxidation of Cobaltite

1987 ◽  
Vol 40 (2) ◽  
pp. 231 ◽  
Author(s):  
AN Buckley
Keyword(s):  
Liquid Nitrogen ◽  
Photoelectron Spectroscopy ◽  
Surface Oxidation ◽  
Dilute Acid ◽  
Ambient Conditions ◽  
Initial Oxidation ◽  
X Ray ◽  
Mineral Sample ◽  
Oxidation In Air ◽  
Aqueous Conditions

The oxidation of cobaltite, CoAsS, has been investigated by X-ray photoelectron spectroscopy. Products of the initial oxidation in air were deduced from surfaces abraded under liquid nitrogen rather than fracture surfaces, as fracture of the mineral sample studied took place preferentially along interfaces at which oxidized material was already present. Cobalt and arsenic oxides are formed in air under ambient conditions; however, sulfur is not involved in the initial oxidation. In air-saturated dilute acid, an oxidized layer is retained at the surface of cobaltite ore particles. Under similar aqueous conditions, pyrite, from which cobaltite often has to be separated, remains free of hydrophilic species.

scholarly journals The Initial Stage in Oxidation of ZrNiSn (Half Heusler) Alloy by Oxygen

Materials ◽  
2019 ◽  
Vol 12 (9) ◽  
pp. 1509 ◽  
Author(s):  
Oshrat Appel ◽  
Gil Breuer ◽  
Shai Cohen ◽  
Ofer Beeri ◽  
Theodora Kyratsi ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Surface Composition ◽  
Surface Oxidation ◽  
Oxide Interface ◽  
X Ray ◽  
Working Temperature ◽  
Initial Stage ◽  
Semiconducting Alloys

The MNiSn (M = Ti; Zr; Hf); half-Heusler semiconducting alloys have a high potential for use as n-type thermoelectric materials at elevated temperatures (~1000 K). The alloys’ durability is crucial for their commercial handling and use, and therefore it is required to characterize their surface oxidation behavior and stability at the working temperature. X-ray photoelectron spectroscopy was utilized to study the surface composition and oxidation of the ZrNiSn alloy at room and elevated temperatures. It was found that during heating in a vacuum, Sn segregates to the surface in order to reduce the surface energy. Exposing the alloy to oxygen resulted mainly in the oxidation of the zirconium to ZrO2, as well as some minor oxidation of Sn. At room temperature, the oxidation to ZrO2 was accompanied by the formation of a thin ZrO layer at the metal-oxide interface. In contrast to TiNiSn, where most of the oxide was formed on the surface due to oxygen-enhanced segregation of Ti, and in the case of ZrNiSn, the formed oxide layer was thinner. Part of the oxide is formed due to Zr segregation to the surface, and in part due to oxygen dissolved into the alloy.

Initial Oxidation of MBE-Grown Si Surfaces

1991 ◽  
Vol 220 ◽  
Author(s):  
T. Igarashi ◽  
H. Yaguchi ◽  
K. Fujita ◽  
S. Fukatsu ◽  
Y. Shiraki ◽  
...  
Keyword(s):  
Electron Diffraction ◽  
Room Temperature ◽  
Elevated Temperatures ◽  
Surface Oxidation ◽  
High Energy ◽  
Photoemission Spectroscopy ◽  
High Energy Electron ◽  
Initial Oxidation ◽  
Mbe Growth ◽  
X Ray

We investigated the initial oxidation of MBE-grown Si (100) surfaces with atomic flatness using x-ray photoemission spectroscopy (XPS) and reflection high energy electron diffraction (RHEED). It was found that the MBE-grown surfaces are inert and hardly oxidized even after exposure to molecular oxygen up to 1500 Langmuir (L) at room temperature. At elevated temperatures, the surface oxidation was substantially promoted. On the contrary, the surface oxidation was found to be substantiated on a deliberately corrugated Si surface prepared by low temperature MBE growth, even at room temperature.

Surface oxidation of a quasicrystalline Al–Cu–Fe alloy:No effect of surface orientation and grain boundaries onthe final state

1999 ◽  
Vol 14 (8) ◽  
pp. 3185-3188 ◽  
Author(s):  
P. J. Pinhero ◽  
J. W. Anderegg ◽  
D. J. Sordelet ◽  
T. A. Lograsso ◽  
D. W. Delaney ◽  
...  
Keyword(s):  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Surface Oxidation ◽  
Surface Orientation ◽  
Final State ◽  
Random Surface ◽  
X Ray ◽  
Significant Difference ◽  
Single Grain ◽  
Effect Of Surface

We have used x-ray photoelectron spectroscopy and Auger electron spectroscopy to examine the characteristics of oxides on two types of quasicrystalline Al–Cu–Fe samples. One type was formed by consolidation of powders, resulting in multiple grains with random surface orientations. The other was a single grain, oriented to expose a fivefold surface. Both were oxidized to saturation in a variety of environments at room temperature. We measured the elemental constituents that oxidized, the extent of oxygen-induced Al segregation, and the depth of the oxide. Under the conditions of our experiments, there was little, if any, significant difference between the two types of samples. Hence, surface orientation and bulk microstructure played little or no role on the final state of the oxide under these conditions.

Oxidation Behavior of a Fe/MnO Ultrathin Film Studied by XPS

1998 ◽  
Vol 05 (01) ◽  
pp. 393-396 ◽  
Author(s):  
V. Di Castro ◽  
S. Ciampi ◽  
L. Sestili
Keyword(s):  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Oxidation Behavior ◽  
Oxygen Adsorption ◽  
Ultrathin Film ◽  
Iron Layer ◽  
Oxide Formation ◽  
Initial Oxidation ◽  
X Ray ◽  
Oxygen Incorporation

The oxidation of a 9-Å-thick iron layer on MnO at room temperature has been investigated by X-ray photoelectron spectroscopy. By exposure to O 2, iron is oxidized first to Fe(II) and then to Fe(III). During the oxide formation a fast oxygen adsorption and initial oxidation to Fe(II) is followed by a slower oxygen incorporation and Fe(III) formation. After exposure to 1500 L O 2 Fe 3 O 4 seems to be formed at the surface, while the iron layer is not completely oxidized.

scholarly journals Non-Thermal Plasma-Modified Ru-Sn-Ti Catalyst for Chlorinated Volatile Organic Compound Degradation

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1456
Author(s):  
Yujie Fu ◽  
You Zhang ◽  
Qi Xin ◽  
Zhong Zheng ◽  
Yu Zhang ◽  
...  
Keyword(s):  
Plasma Treatment ◽  
Photoelectron Spectroscopy ◽  
High Surface ◽  
High Surface Area ◽  
Surface Oxidation ◽  
Treatment Method ◽  
X Ray ◽  
Chlorinated Volatile Organic Compounds ◽  
Volatile Organic ◽  
Doped Titania

Chlorinated volatile organic compounds (CVOCs) are vital environmental concerns due to their low biodegradability and long-term persistence. Catalytic combustion technology is one of the more commonly used technologies for the treatment of CVOCs. Catalysts with high low-temperature activity, superior selectivity of non-toxic products, and resistance to chlorine poisoning are desirable. Here we adopted a plasma treatment method to synthesize a tin-doped titania loaded with ruthenium dioxide (RuO2) catalyst, possessing enhanced activity (T90%, the temperature at which 90% of dichloromethane (DCM) is decomposed, is 262 °C) compared to the catalyst prepared by the conventional calcination method. As revealed by transmission electron microscopy, X-ray diffraction, N2 adsorption, X-ray photoelectron spectroscopy, and hydrogen temperature-programmed reduction, the high surface area of the tin-doped titania catalyst and the enhanced dispersion and surface oxidation of RuO2 induced by plasma treatment were found to be the main factors determining excellent catalytic activities.

scholarly journals Synthesis of Magnetic Ferrocene-Containing Polymer with Photothermal Effects for Rapid Degradation of Methylene Blue

Polymers ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 558
Author(s):  
Wenhui Zhu ◽  
Caiyun Zhang ◽  
Yali Chen ◽  
Qiliang Deng
Keyword(s):  
Methylene Blue ◽  
Photoelectron Spectroscopy ◽  
Room Temperature ◽  
Degradation Rate ◽  
Model Compound ◽  
Vibrating Sample Magnetometer ◽  
Simulated Sunlight ◽  
X Ray Diffraction ◽  
X Ray ◽  
Ft Ir

Photothermal materials are attracting more and more attention. In this research, we synthesized a ferrocene-containing polymer with magnetism and photothermal properties. The resulting polymer was characterized by Fourier-transform infrared (FT-IR), vibrating sample magnetometer (VSM), scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). Its photo-thermocatalytic activity was investigated by choosing methylene blue (MB) as a model compound. The degradation percent of MB under an irradiated 808 nm laser reaches 99.5% within 15 min, and the degradation rate is 0.5517 min−1, which is 145 times more than that of room temperature degradation. Under irradiation with simulated sunlight, the degradation rate is 0.0092 min−1, which is approximately 2.5 times more than that of room temperature degradation. The present study may open up a feasible route to degrade organic pollutants.

scholarly journals A Highly Sensitive Room Temperature CO2 Gas Sensor Based on SnO2-rGO Hybrid Composite

Materials ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 522
Author(s):  
Zhi Yan Lee ◽  
Huzein Fahmi bin Hawari ◽  
Gunawan Witjaksono bin Djaswadi ◽  
Kamarulzaman Kamarudin
Keyword(s):  
Electron Microscopy ◽  
Carbon Dioxide ◽  
Gas Sensor ◽  
Photoelectron Spectroscopy ◽  
Hybrid Composite ◽  
Room Temperature ◽  
Co2 Gas ◽  
X Ray ◽  
Wide Range ◽  
Co2 Gas Sensor

A tin oxide (SnO2) and reduced graphene oxide (rGO) hybrid composite gas sensor for high-performance carbon dioxide (CO2) gas detection at room temperature was studied. Since it can be used independently from a heater, it emerges as a promising candidate for reducing the complexity of device circuitry, packaging size, and fabrication cost; furthermore, it favors integration into portable devices with a low energy density battery. In this study, SnO2-rGO was prepared via an in-situ chemical reduction route. Dedicated material characterization techniques including field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray (EDX) spectroscopy, Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) were conducted. The gas sensor based on the synthesized hybrid composite was successfully tested over a wide range of carbon dioxide concentrations where it exhibited excellent response magnitudes, good linearity, and low detection limit. The synergistic effect can explain the obtained hybrid gas sensor’s prominent sensing properties between SnO2 and rGO that provide excellent charge transport capability and an abundance of sensing sites.

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