Paper surface electron spectroscopy

We have undertaken a series of experiments Involving thin film models of such powdered transition metal catalysts (13,14). In this paper we present a brief review of the results we have obtained to date Involving platinum and rhodium deposited on thin films of tltanla, the latter prepared by oxidation of a tltanliua single crystal. These systems are prepared and characterized under well-controlled conditions. We have used thermal desorption spectroscopy (TDS), Auger electron spectroscopy (AES) and static secondary Ion mass spectrometry (SSIMS). Our results Illustrate the power of SSIMS In understanding the processes that take place during thermal treatment of these thin films. Thermal desorption spectroscopy Is used to characterize the adsorption and desorption of small molecules, In particular, carbon monoxide. AES confirms the SSIMS results and was used to verify the surface cleanliness of the films as they were prepared. 

The early papers usually assumed that surface concentration can be estimated from the normalized ratio of the Auger peaks (41,42). However, soon it appeared that this had led to incorrect conclusions on, e.g., Ni-Cu (43) or Pd-Ag (44) alloys. In particular, the progress with pure Ni-Cu alloy systems suffered very much from the uncertainties caused by improper procedures. The main point to keep in mind in this respect is that the ratio of peak intensities for metals A and B in alloys related to those in the pure metals, as seen by Auger electron spectroscopy (AES), is given by (45, 47) the following equation ... 

In this paper the hydroxide concentration dependence of the rate of hydrogen production in SrTi03 systems (12) is discussed in light of surface analytical results. The surface elemental composition before and after illumination in various aqueous electrolytes has been monitored with Auger electron spectroscopy... 

Theories and instrumentation of Fourier transform IR spectroscopy and electron spectroscopy for chemical analysis are briefly reviewed. The possibility of using these techniques in detection and analysis of acid impurities distributed at surfaces of paper documents produced during the period from 1790 to 1983 is demonstrated. Results show that all of the papers tested contained carboxylic groups. The carboxylic acids found in the paper of 1790 are the results of oxidation and aging. Acids in other papers are due to fiber oxidation as well as the presence of rosin acids. These techniques show promise as nondestructive methods for elucidating chemical characteristics of surfaces of paper documents. 

The measurement of acidity in paper documents with cold- and hot-water extraction frequently distorts and damages the paper fibers and printing inks. Many paper conservators and museum curators have long desired a reliable and rapid method for the detection of acidity of paper documents in a nondestructive manner so that they can determine the acidity routinely to screen out valuable book documents for deacidification or other necessary preservation treatments. The objective of this chapter is to introduce two spectroscopic techniques, namely, Fourier transform IR spectroscopy (FTIR) and electron spectroscopy for chemical analysis (ESCA), for chemical analysis of paper surfaces. The effectiveness of these techniques in analyzing and determining the presence of acidic functional groups on paper documents is demonstrated. 

Surface Chemistry of Business Papers Electron Spectroscopy for Chemical Analysis Studies... 

The present paper reviews the physical and chemical evidence for the above rules obtained over the last several years from ultrahigh vacuum surface science studies of molybdenum single crystals chemically modified by 0, C, S, and B. Additionally, the results of recent studies of methylcyclopropane hydrogenolysis will be presented which illustrate the influence of surface acid/base sites on catalytic hydrocarbon conversions. The surface coverage of each modifier was determined by quantitative Auger electron spectroscopy or x-ray photoelectron spectroscopy (XPS). The atomic structure of oxygen, carbon, and sulfur adlayers below one monolayer (ML)... 

Spectroscopy (IR), Raman Spectroscopy, X-ray Photoelectron Spectroscopy (XPS) or Electron Spectroscopy for Chemical Analysis (ESCA), and Secondary Ion Mass Spectrometry (SIMS). More recently. Atomic Force Microscopy (AFM) has also found important use in the characterization of the local surface distribution of paper. Below, we will briefly discuss the use of some different surface-sensitive techniques in paper applications and relate the results obtained to paper characteristics and end-use properties. For a more detailed description of these and other available techniques for characterizing the chemistry of paper surfaces, readers are referred to ref. (60). 

ABSTRACT. The paper details the use of scanning electron microscopy, surface reflectance infrared spectroscopy, Auger electron spectroscopy, ion scattering spectroscopy, secondary ion mass spectroscopy, and x-ray photoelectron spectroscopy in the analysis of polymeric adhesives and composites. A brief review of the principle of each surface analytical technique will be followed by application of the technique to interfacial adhesion with an emphasis on polymer/metal, fiber/matrix, and composite/composite adhesion. 

All experiments in this paper were performed in an UHV surface analysis instrument equipped with a Phi model 3017 Auger electron spectroscopy subsystem and Phi model 15-120 low energy electron diffraction EED) optics. The instrument was also equipped with an electrochemical antechamber used to perform the etching experiments (1,26,27). A standard, in-house built, three electrode... 

The primary motivation of this paper is to illustrate the use and to showcase the power of UHV-STM-EC, even in a less-than-ideal scenario in which the UHV and STM experiments were performed separately in two different laboratories. The case studied involves the dissolution of Pd(llO) that occurs only when a monolayer of iodine is present on the surface [7,8]. The structural and compositional features of the halogen-metal interface that characterize the adsorbate-catalyzed corrosion were first explored with low-energy electron diffraction (LEED) and Auger electron spectroscopy (AES) initial- and final-state measurements were quite easily obtained. Certain questions, however, such as the mechanism for dissolution, necessitated an in situ technique for answers it was in this regard that the STM-EC work was prompted. 

In conclusion, we present a list of papers devoted to the electronic structure of carbides and nitrides surface investigated by electron (PES, ARPES) and Auger electron spectroscopy (AES) methods ... 

The paper presented by J. P. Wightman e aT, examines metal surface before and after bonding with polyimide resins. Again, as in the previous paper, the critical nature of the boundary layer between the adhesive and the metal surface becomes evident. By use of scanning electron microscopy, electron spectroscopy for chemical analyses, and reflectance infrared spectroscopy, the actual surface and boundary layers are examined. This paper develops experimental and theoretical criteria for evaluating new cured adhesives. 

Of special Interest as O2 reduction electrocatalysts are the transition metal macrocycles In the form of layers adsorptlvely attached, chemically bonded or simply physically deposited on an electrode substrate Some of these complexes catalyze the 4-electron reduction of O2 to H2O or 0H while others catalyze principally the 2-electron reduction to the peroxide and/or the peroxide elimination reactions. Various situ spectroscopic techniques have been used to examine the state of these transition metal macrocycle layers on carbon, graphite and metal substrates under various electrochemical conditions. These techniques have Included (a) visible reflectance spectroscopy (b) laser Raman spectroscopy, utilizing surface enhanced Raman scattering and resonant Raman and (c) Mossbauer spectroscopy. This paper will focus on principally the cobalt and Iron phthalocyanlnes and porphyrins. 

J. W. Linnett. There were 11 papers with theoretical inputs but with more emphasis given to new developments in experimental methods including structural (LEED and electron microscopy) and surface spectroscopies. LEED provided crucial evidence for the role of surface steps at platinum single crystals in the dissociation of various diatomic molecules, while electron microscopy revealed the role of dislocations as sites of high reactivity of... 

This book deals only with the chemistry of the mineral-water interface, and so at first glance, the book might appear to have a relatively narrow focus. However, the range of chemical and physical processes considered is actually quite broad, and the general and comprehensive nature of the topics makes this volume unique. The technical papers are organized into physical properties of the mineral-water interface adsorption ion exchange surface spectroscopy dissolution, precipitation, and solid solution formation and transformation reactions at the mineral-water interface. The introductory chapter presents an overview of recent research advances in each of these six areas and discusses important features of each technical paper. Several papers address the complex ways in which some processes are interrelated, for example, the effect of adsorption reactions on the catalysis of electron transfer reactions by mineral surfaces. 

After the first theoretical work of Tamm (1932), a series of theoretical papers on surface states were published (for example, Shockley, 1939 Goodwin, 1939 Heine, 1963). However, there has been no experimental evidence of the surface states for more than three decades. In 1966, Swanson and Grouser (1966, 1967) found a substantial deviation of the observed fie Id-emission spectroscopy on W(IOO) and Mo(lOO) from the theoretical prediction based on the Sommerfeld theory of metals. This experimental discovery has motivated a large amount of theoretical and subsequent experimental work in an attempt to explain its nature. After a few years, it became clear that the observed deviation from free-electron behavior of the W and Mo surfaces is an unambiguous exhibition of the surface states, which were predicted some three decades earlier. 

In our previous paper (ref. 2) we demonstrated the particular role played by one-electron donor centres on magnesia surface in catalytic transfer hydrogenation. Moreover, nitroarenes exhibit high tendency to convert themselves into corresponding anion radicals during adsorption on MgO. Thus, it was expected that esr spectroscopy would reveal new data concerning the reactants activation. 

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