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X-ray absorption near the edge structure and x-ray photoelectron spectroscopy studies on pyrite prepared by thermally sulfurizing iron films 下载免费PDF全文
This paper reports how pyrite films were prepared by thermal
sulfurization of magnetron sputtered iron films and characterized by
x-ray absorption near edge structure spectra and x-ray photoelectron
spectroscopy on a 4B9B beam line at the Beijing Synchrotron Radiation
Facility. The band gap of the pyrite agrees well with the optical
band gap obtained by a spectrophotometer. The octahedral symmetry of
pyrite leads to the splitting of the d orbit into t_{\rm 2g} and
e_{\rm g} levels. The high spin and low spin states were analysed
through the difference of electron exchange interaction and the orbital
crystal field. Only when the crystal field splitting is higher than
1.5 eV, the two weak peaks above the white lines can appear, and this
was approved by experiments in the present work. 相似文献
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Platinum oxide-titanium films that are produced by thermolysis of H2PtCl6 in the presence of NO
3
−
on a titanium surface are investigated by the method of x-ray photoelectron spectroscopy. It is shown that making nitrates
a part of the composition leads to an increase in the content of oxidized forms of platinum and the appearance of titanium
in the film.
Belarusian State Technological University, 13a, Sverdlov St., Minsk, 220630, Belarus. Translated from Zhurnal Prikladnoi Spektroskopii,
Vol. 64, No. 4, pp. 536–538, July–August, 1997. 相似文献
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Katsumi Kimura 《Journal of Electron Spectroscopy and Related Phenomena》1999,100(1-3):273-296
This review article is mainly concerned with laser photoelectron spectroscopy based on REMPI (resonantly enhanced multiphoton ionization), consisting of two parts. One is associated with the measurement of photoelectron kinetic-energy distribution and the other is associated with the measurement of zero-kinetic-energy (ZEKE) photoelectrons in very high resolution. These two techniques are complementary to each other. During the last three decades, the author and co-workers have carried out photoelectron spectroscopic studies of molecules in the gas phase, using the HeI 584 Å resonance line and a nanosecond tunable UV–visible laser. In this article, firstly the author’s background in the field of molecular photoelectron spectroscopy is described briefly, by mentioning three topics of HeI photoelectron spectroscopy. Secondly, the principle and characteristics of laser photoelectron kinetic-energy spectroscopy and its application to several typical topics, namely, one-photon forbidden states (O2), autoionization from a super-excited state (NO), and small van der Waals molecules (NO–Ar and the NO2 dimer), and some others. Thirdly, the principle and characteristics of ZEKE photoelectron spectroscopy are described, together with its application to the following several topics: (1) rotational spectra of NO+, (2) vibrational coupling of (naphthalene)+, (3) large-amplitude torsional motion of (tolane)+, (4) rotational isomers of (cis and trans n-propylbenzene)+ and structural isomers of (2-hydroxypyridine)+, (5) proton tunneling of (tropolone)+ and (9-hydroxyphenalenone)+, (6) intramolecular vibrational redistribution of trans stilbene, and (7) cation van der Waals molecules of aniline–Arn (n=1,2) and azulene–Ar. All the results mentioned as examples are those obtained in the author’s laboratory. 相似文献
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X-ray and ultraviolet photoelectron spectroscopy have been employed to investigate the high temperature metal-insulator transitions
in V2O3 and (V0.99Cr0.01)2O3. The high temperature transitions are associated with more gradual changes in the 3d bands compared to the low-temperature transitions.
Communication No. 20 from Solid State & Structural Chemistry Unit. 相似文献
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用高温熔融、淬火、扩散退火结合放电等离子烧结(SPS)法合成了Ca和Ce复合填充的单相CamCenFexCo4-xSb12(m=0.17—0.27,n=0.05—0.25,x=1.5)化合物,并结合Rietveld结构解析以及X射线光电子能谱(XPS)分析研究了两种原子复合填充skutterudite化合物的结构与填充状态.Rietveld结构解析表明,CamCenFe1.5Co2.5Sb12化合物具有skutterudite结构,Ca和Ce原子填充到了Sb的二十面体空洞中,填充原子热振动参数BCa/Ce远大于框架原子的热振动参数BFe/Co和BSb.XPS元素窄区谱分析结果表明,Sb原子在结构中有五种化学状态,每种化学状态的相对含量主要由总填充分数决定,填充原子Ca在Sb的二十面体空洞出现概率有三种可能,但在中心位置出现的概率最大.
关键词:
skutterudite化合物
双原子复合填充
结构
X射线光电子能谱分析 相似文献
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W H Madhusudan Sheelavathi Kollali P R Sarode M S Hegde P Ganguly C N R Rao 《Pramana》1979,12(4):317-329
X-ray and ultraviolet photoelectron spectroscopy as well as x-ray absorption spectroscopy have been employed to investigate
transition metal oxide perovskites of the general formula ABO3 (A = La or rare-earth ion, B=trivalent transition metal ion). Systematics in the core levels and in the valence bands in
the series of LaBO3 compounds have been discussed. Lanthanum chemical shifts in the x-ray absorption spectra in this series show interesting
trends. Photoelectron spectra of the solid solutions, LaNi1−x
Co
x
O3, LaNi1−x
Fe
x
O3 and LaFe1−x
Co
x
O3 show that the rigid band model is applicable to these systems. It is shown that x-ray photoelectron spectroscopy can be employed
to identify multiple oxidation states of transition metal ions in oxide perovskites.
Communication No. 30 from the Solid State and Structural Chemistry Unit.
An erratum to this article is available at . 相似文献
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Core-shell nanostructures were grown in silica-based glasses. Copper-copper oxide and iron-iron oxide structures had diameters in the range 3-6 nm, with shell thicknesses ∼1-2 nm. Silver-lithium niobate core-shell nanostructures had diameters in the range 4.2-46 nm and thicknesses varying from 2.2 to 22 nm. X-ray photoelectron spectroscopy studies were carried out on all these specimens. The analyses of these results show the presence of Cu+/Cu2+, Fe2+/Fe3+ and Nb4+/Nb5+ valence states in the above three systems. Electrical resistivity data were fitted satisfactorily to the small polaron hopping model in the case of copper and iron-containing specimens. The presence of ions in the lithium niobate shell provides direct evidence of the formation of localized states between which variable range hopping conduction can be effected. 相似文献
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Although X-ray photoelectron spectroscopy of polymers was well established by Clark and coworkers in the 1970s, ultraviolet photoelectron spectroscopy of polymer films, was developed later. Previous to the 1970s, the first attempts to use ultraviolet light on polymer films took the form of appearance potential (valence band edge) measurements. Only some years later could the full valence band region of thin polymer films, including insulating polymers, semiconducting polymers and electrically conducting polymers. The development of what might be termed “classical ultraviolet photoelectron spectroscopy” of polymer films may be loosely based upon a variety of issues, including adapting thin polymer film technology to ultra high vacuum studies, the widespread use of helium resonance lamps for studies of solid surfaces, the combined advent of practical and sufficient theoretical–computational methods. The advent of, and the use of, easily available synchrotron radiation for multi-photon spectroscopies, nominally in the area of the near UV, is not included in the term “classical”. At the same time, electrically conducting polymers were discovered, leading to applications of the corresponding semiconducting polymers, which added technologically driven emphasis to this development of ultraviolet photoelectron spectroscopy for polymer materials. This paper traces a limited number of highlights in the evolution of ultraviolet photoelectron spectroscopy of polymers, from the 1970s through to 2008. Also, since this issue is dedicated to Prof. Kazuhiko Seki, who has been a friend and competitor for over two decades, the author relies on some of Prof. Seki's earlier research, unpublished, on who-did-what-first. Prof. Seki's own contributions to the field, however, are discussed in other articles in this issue. 相似文献
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Characteristics of the atomic structure of lead-silicate glasses, among them the concentration of lead structural forms, the
statistics of both silicon-oxygen and lead-oxygen structures of medium-range ordering, and the bonding degrees of silicon-oxygen
and lead-oxygen structures, have been found using x-ray photoelectron spectroscopy and thermodynamic simulation.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 76, No. 2, pp. 209–217, March–April, 2009. 相似文献
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Thomas A. Carlson J.C. Carver Leif J. Saethre F.Garcia Santibánez G.A. Vernond 《Journal of Electron Spectroscopy and Related Phenomena》1974,5(1):247-258
This paper is a summary of work in progress on a comprehensive study of the nature of satellite lines in x-ray photoelectron spectroscopy. The work can be broken down into three principal areas: (1) The satellite structure arising from photoionization in the K shell of transition metal compounds has been measured using CuKα x rays. From these data the relative importance of electron shake up and multiples splitting has been ascertained. (2) A systematic study of the satellite structure following photoionization in the 2p subshell of the metal ion for first row transition metal halides, hexacyano complexes, acetyl acetonates and other miscellaneous compounds. The data can be explained in terms of monopole excitation involving either charge exchange between ligand and metal orbitals or excitation of electrons in the 3d orbital. (3) A study of multiplet splitting in the 3s subshell of nickel for a series of NiFexCr 2-xO4 alloys has been carried out and compared with measurements on the hyper field interactions from Mössbauer experiments. 相似文献
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Chemical compositions of the alloys of CuNi (Cu0.10Ni0.90, Cu0.30Ni0.70, Cu0.70Ni0.30) and BiSb (Bi0.80Sb0.20, Bi0.64Sb0.34, Bi0.55Sb0.45) are determined by X-ray photoelectron spectroscopy. The stoichiometries are determined and are compared with the bulk compositions.
Possible sources of systematic errors contributing to the results are discussed. Errors arising out of preferential etching
in these alloys have been investigated. It has been inferred from such studies that the preferential etching does not enrich
the surface composition with a particular component for the two systems reported here. Quantitative results of CuNi system
indicate that the surface regions of the Cu0.70Ni0.30 alloy is Cu-rich, although no such evidence is observed in case of BiSb system. 相似文献
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The formidable challenge of developing high-performance battery system stems from the complication of battery operations, both mechanically and electronically. In the electrodes and at the electrode–electrolyte interfaces, chemical reactions take place with evolving electron states. In addition to the extensive studies of material synthesis, electrochemical, structural, and mechanical properties, soft x-ray spectroscopy provides unique opportunities for revealing the critical electron states in batteries. This review discusses some of the recent soft x-ray spectroscopic results on battery binder,transition-metal based positive electrodes, and the solid-electrolyte-interphase. By virtue of soft x-ray's sensitivity to electron states, the electronic property, the redox during electrochemical operations, and the chemical species of the interphases could be fingerprinted by soft x-ray spectroscopy. Understanding and innovating battery technologies need a multimodal approach, and soft x-ray spectroscopy is one of the incisive tools to probe the chemical and physical evolutions in batteries. 相似文献
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含铀(U)薄膜在激光惯性约束聚变的实验研究中有重要的用途.研究其在不同气氛下的氧化性能可以为微靶制备、储存及物理实验提供关键的实验数据.通过超高真空磁控溅射技术制备了纯U薄膜及金-铀(Au-U)复合平面膜,将其在大气、高纯氩(Ar)气及超高真空度环境中暴露一段时间后,利用X射线光电子能谱仪结合Ar~+束深度剖析技术考察U层中氧(O)元素分布及价态,分析氧化产物及机理.结果显示,初始状态的U薄膜中未检测到O的存在.Au-U复合薄膜中的微观缺陷减弱了Au防护层的屏蔽效果,使其在3周左右时间内严重氧化,产物为U表面致密的氧化膜及缺陷周围的点状腐蚀物,主要成分均为二氧化铀(UO_2).在高纯Ar气中纯U薄膜仅暴露6 h后表面即被严重氧化,生成厚度不均匀的UO_2.在超高真空度环境下保存12 h后,纯U薄膜表面也发生明显氧化,生成厚度不足1 nm的UO_2.Ar~+束对铀氧化物的刻蚀会因择优溅射效应而使UO_2被还原成非化学计量的UO_(2-x),但这种效应受O含量的影响. 相似文献
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Surface films on metals and alloys often protect them from reaction with the environment, and hence a knowledge of their protective
properties and composition could be invaluable for predicting their corrosion behaviour. XPS (x-ray photoelectron spectroscopy)
could provide a quantitative analysis of the chemical composition, the nature of valence states and elemental distribution
within the surface films.
The present paper reviews the potential of this technique in corrosion studies. A brief review of the work done on the passivation
of iron and iron-chromium alloys and on the inhibition studies on copper base alloys has been given. A few examples of investigations
carried out at authors’ laboratory are also included. An attempt has been made to establish a correlation between the compositions
of the films formed and corrosion behaviour of carbon steel in 10.5 pH lithium hydroxide solution and of Cu-Ni alloys and
sacrificial Al-Zn-Sn alloys in synthetic sea-water. 相似文献
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Accurate measurement of work function is essential in many areas of research and development. Despite the importance of photoelectron spectroscopy as a technique for measuring work function, there has been relatively little discussion in the literature of how to conduct accurate measurements. We review the basic technique of measuring work function using ultraviolet photoelectron spectroscopy and discuss several common sources of error related to the experimental setup. In particular, the sample-detector geometry is found to be a key experimental parameter; accurate results are only obtained when the sample is perpendicular to the electron detector. In addition, we demonstrate that photoelectron work function values correspond to the minimum work function “patch” on a non-uniform surface, in contrast to the average work function measured by other techniques, such as the Kelvin probe method. 相似文献
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用X射线光电子能谱和同步辐射光电子能谱研究了Sb掺杂的钙钛矿型氧化物SrTi1-xSbxO3(x=0.05,0.10,0.15,0.20)薄膜的电子结构.薄膜由紫外脉冲激光淀积在SrTiO3(001)单晶衬底上.该薄膜系列在可见光波段透明,透过率均超过90%.其导电性与掺杂浓度有关,当Sb掺杂浓度x=0.05时,薄膜显示金属型导电性.X射线光电子能谱和同步辐射光电子能谱研究结果表明,Sb掺杂在母化合物SrTiO3的禁带内引入了浅杂质能级和深杂质能级.浅杂质能级上的退局域化电子离化到导带中会产生一定的传导电
关键词:
光电子能谱
光学透过率
脉冲激光沉积薄膜 相似文献