Surface science instrumentation

X-ray Photoelectron Spectroscopy analysis of the samples was performed with a Surface Science Instruments spectrometer (SSI 100) with a resolution (FWHM Au 4f7/2) of 1.0 eV. The X-ray beam was a monochromatised AlKa radiation (1486.6 eV). A charge neutraliser (flood gun) was adjusted at an energy of 6 eV. As the Cls spectra of these compounds were very complex, the binding energies were referenced to the binding energy of Ols, considered experimentally to be at 531.8 eV [8). 

A Surface Science Instruments SSX-100 spectrometer (model 206), equipped with an aluminum anode whose radiation was monochromatized (AlKa, 1486.6 eV) and focalized, was used. The positive charge developed at the surface of the samples was compensated with a charge neutralizer adjusted at an energy of 8 eV. 

XPS of NH3 adsorption was carried out on a SSI (Surface Science Instrument) spectrometer. NH3 was adsorbed at 80 °C on the calcined samples and then outgassed under helium at 350 °C. The proportion of each type of site (Bronsted and Lewis) was evaluated by analyzing the Nls band. 

This unit will introduce two fundamental protocols—the Wilhelmy plate method (see Basic Protocol 1 and Alternate Protocol 1) and the du Noiiy ring method (see Alternate Protocol 2)—that can be used to determine static interfacial tension (Dukhin et al., 1995). Since the two methods use the same experimental setup, they will be discussed together. Two advanced protocols that have the capability to determine dynamic interfacial tension—the drop volume technique (see Basic Protocol 2) and the drop shape method (see Alternate Protocol 3)—will also be presented. The basic principles of each of these techniques will be briefly outlined in the Background Information. Critical Parameters as well as Time Considerations for the different tests will be discussed. References and Internet Resources are listed to provide a more in-depth understanding of each of these techniques and allow the reader to contact commercial vendors to obtain information about costs and availability of surface science instrumentation. 

XPS analysis of y-APS applied to nickel and silicon substrates was also carried out using a Surface Science Instruments SSX-100-03 instrument equipped with a monochromatic A1 Ka source. The X-ray source had an energy of 1487 eV and the instrument operated at a spot size of 600 //m. Pass energies for survey and high resolution spectra were 150 and 52 eV, respectively. Atomic concentrations were once again obtained from the high resolution spectra using sensitivity factors provided with the software. 

The position of a nickel Auger peak superimposed on the N(ls) photoelectron peak was detected when spectra of coated nickel samples were collected on the Physical Electronics Model 5300 ESCA system using Mg Ka X-rays. Therefore, XPS spectra of nickel samples were obtained using a Surface Science Instruments SSX-100-03 instrument equipped with a monochromatic A1 Ka source. The N(ls) high-resolution spectra obtained from polished nickel which had been coated with y-APS from a 1% aqueous solution at pH 10.4 are shown in Fig. 8. 

The XPS analyses of the catalyst samples were performed on a Surface Science Instruments spectrometer (SSX 100) with a resolution (FWHM Au 4f-jp) of 1.0 eV. The X-ray... 

X-ray photoelectron spectroscopy (XPS) measurements were performed using a SSX-100 model 206 Surface Science Instrument Spectrometer operated at 10 kV, 12 mA with a monochromatized A1 Ka radiation (1486.6 eV). The catalysts were pressed into the samples holders of 6 mm and then introduced into the preparation chamber of the spectrometer. The Cu, Mosd, Co2p, Niap and Ou lines were recorded for each sample. All binding energies were referenced to the Cu level at 284.8 eV. Surface composition was determined from the peak intensities and the Scofield sensitivity factors provided by the instrument software. For spectrum deconvolution, a Shirley baseline was used and peaks were considered Gaussian/ Lorentzian ratio of 85/15. 

At this stage in the literature, we find that both STM and AFM can operate for fluids, which is technically impossible by electron microscope. This means that, for the first time in history, molecular dimensional analyses of surfaces and molecules situated at surfaces can be carried out in a liquid. This most important discovery in surface science instrumentation allows us to see... 

In our x-ray photoemission studies, a monochromatized photon beam (A1 Ka, hv = 1486.6 eV) was focused onto the sample surface, and the emitted electrons were energy analyzed with a Surface Sciences Instruments hemispherical analyzer. The take-off angle of the photoelectrons relative to the surface normal was 60° unless otherwise specified. A position-sensitive detector with 128 channels was used with a dedicated HP9836C computer to facilitate data acquisition. (22.) ... 

X-ray photoelectron spectroscopy. The analyses were performed on a SSX 100/206 photoelectron spectrometer from Surface Science Instruments. The binding energies were calculated with respect to the C-(C,H) component of C Is peak fixed at 284.8 eV. The spectra were decomposed with the least squares fitting routine provided by CasaXPS software with a Gaussian/Lorentzian (85/15) product function and after subtraction of a non linear baseline. 

BET surface area was measured with the single point method, using a Micromeritics Flow Sorb II2300. XRD patterns were recorded using a Siemens D-5000 powder diffractometer equipped with a Ni-filtered Cu Ka source. XPS spectra were collected on a SSX-100 Model 206 Surface Science Instrument... 

Because many surface probes require high vacuum during their application, most surface science instruments are also equipped with high-pressure or environmental cells. The sample to be analyzed is first subjected to the usual high-pressure and/or high-temperature conditions encountered during reactions in the environmental cell. Then it is transferred into the evacuated chamber where the surface probe is located for surface analysis. One such apparatus is shown in Figure 1.13. 

This pioneering work shows that the chemisorption of even one of the reactants, CO, in the FTS is not a simple process. Since this work, the introduction of surface science instrumentation employing single crystals of metals active for FTS has led to hundreds of papers per year on CO adsorption and desorption, and many of these are concerned with the isotope exchange reaction of CO. While this is an important aspect of FTS and many of the studies utilize isotopes, this will not be covered since it represents a special area within the overall FTS. A historical view of the chemisorption of CO on surfaces has appeared recently. ... 

X-ray Photoelectron Spectroscopy (XPS) spectra were recorded using a Surface Science Instrument SSX-100. This system produces monochromatic A1 Ka X-ray with energy of 1486.6eV. This instrument was operated using a 300 pm X-ray spot for all experiments. In the experiment, Ar ion etching was used to remove material to examine the relative composition within the film. The... 

Because of the wide variety of surface modification and analysis techniques and the even wider variety of applications, surface science has had a far-reaching but difficult to quantify impact on industry. The majority of the impact comes from the power of the techniques to help scientists and engineers improve processes and solve problems rather than from marketing surface science instrumentation to the general public. 

Fig. 7 X-ray photoelectron spectrometer. Left schematic view of a SSX 100/206 (Surface Science Instruments). Right, photographs of a Kratos Axis Ultra (Kratos Analytical) with the introduction and intermediate chambers (top) and analysis chamber (bottom), a, Turbomolecular pump b, cryogenic pump c, introduction chamber d, sample analysis chamber (SAC) e, transfer probe f, automatized X, Y, Z manipulator g, X-ray monochromator h, electrostatic lens i, hemispherical analyzer (HSA) j, ion gun k, aluminum anode (with monochromator) 1, aluminum-magnesium twin anode m, detector. Left channel plate. Right 8 channeltrons (Spectroscopy mode), phosphor screen behind a channel plate with a video camera (Imaging mode) n, spherical mirror analyzer (SMA) o, parking facility in the sample transfer chamber p, sample cooling device for the introduction chamber q, sample transfer chamber r, monitor interconnected with the video camera viewing samples in the SAC s, video camera in the SAC t, high temperature gas ceU (catalyst pretreatment)...

The Surface Science Instruments (SSI) (part of the Thermo group) m-probe focuses the x-rays to a spot of diameter ca. 100 pm on the specimen surface. Rastering to form a two-dimensional image is not carried out in the source or the analyzer lens, but is achieved by moving the specimen stage with stepper... 

X-ray photoelectron spectroscopy (XPS) analysis was carried out using an ESCA system (XI ASCII Surface Science Instruments) with an operating pressure of between 10 and 10 Torr, fitted with A1 anode (1486.6 eV) and giving an energy resolution of 1 eV. 

The XRD patterns were obtained on a D8 Advance diffractometer (Bmker) using CuKa radiation ( =0.154 mn). Scanning Electron Microscopy (Philips SEM 515) operating at 15 kV was applied. A1 NMR spectra were recorded using Bmker Avance DPX300 spectrometer. UV-Vis spectra were scanned by a Varian-Caty 300 Scan UV-Visible Spectrophotometer. The XPS analyses were performed with a SSI-X-probe (SSX-100/ 206) photoelectron spectrometer equipped with a monochromatic microfocused Al Ka X-ray source (1486.6 eV) from Surface Science Instruments. EllK spectra were obtained on Bmker Vector 22 spectrometer. 

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