X-ray photo-emission spectroscopy

MAGNETIC DICHROISM IN VALENCE BAND X-RAY PHOTO EMISSION SPECTROSCOPY... 

The characterization of graphene often involves several techniques in conjunction in order to build up a complete picture of the material. The techniques typically include electron microscopy, Raman spectroscopy, X-ray photo-emission spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR) and thermal-gravimetric analysis (TGA). 

XRD, X-ray diffraction XRF, X-ray fluorescence AAS, atomic absorption spectrometry ICP-AES, inductively coupled plasma-atomic emission spectrometry ICP-MS, Inductively coupled plasma/mass spectroscopy IC, ion chromatography EPMA, electron probe microanalysis SEM, scanning electron microscope ESEM, environmental scanning electron microscope HRTEM, high-resolution transmission electron microscopy LAMMA, laser microprobe mass analysis XPS, X-ray photo-electron spectroscopy RLMP, Raman laser microprobe analysis SHRIMP, sensitive high resolution ion microprobe. PIXE, proton-induced X-ray emission FTIR, Fourier transform infrared. 

SnC>2 nanoparticles have been successfully synthesized by chemical co-precipitation method using ethanol, acetone, tetrahydrofuran (THF) and ether as solvents. X-ray Diffraction (XRD), Field Emission Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM) have been used to study the crystallographic and morphological properties of synthesized SnC>2 nanoparticles, while their optical properties have been studied by UV-Visible absorption spectroscopy. UV-Vis absorption spectra shows a weak quantum confinement in all the synthesized SnCL samples. The photo-catalytic activity of as-synthesized SnC>2 nanoparticles under UV irradiation has been evaluated using Methylene Blue (MB) dye as a test contaminant in water. The results showed that solvents played a key role to control the morphology and photo-catalytic activity of SnCE nanoparticles. 

X-Ray Photoelectron Spectroscopy (XPS) This method is based upon the photoelectric effect (see Fig. 3a), which is activated by low-energy X-radiation (usually A1 Ka or Mg Ka radiation). The specimen chamber is evacuated. The released electrons are emitted into the vacuum (photo emission), where their energy is determined by use of an electron spectrometer, comparable to AES. Quantitative determination of the chemical composition requires substantial corrections of the measured spectrum (Briggs and Grant 2003). By variations of the incident angle, this method can deliver very surface-near information (monolayer). 

The principle of X-ray photoelectron spectroscopy (XPS) is a well-known photoelectric effect, in which the sample is irradiated by a source of low-energy X-rays that leads to the emission of electrons from the lower energy atomic orbitals, as shown schematically in Fig. 4.9b. The kinetic energy of the emitted photo-electrons, Ek, is given by ... 

The actual Fe content of doped Ti02 was determined by atomic absorption flame emission spectroscopy (Shimadzu AA-6400F). X-ray diffraction patterns of materials were measttred with a Shimadzu XRD-6100 analyzer with Cu K radiation (1=1.5417A). The X-ray photoelectron spectroscopic (XPS) investigations were carried out with a Shimadzu ESCA-3200 spectrometer in order to analyze the sttrface elemerrtal composition and valence state of elements of the photo catalysts. Diffuse reflectance UV-vis spectra of the catalysts were measured using a Shimadzu UV-2200A and a Shimadzu UV-vis spectrophotometer. The FT-IR spectra of the samples were measttred using KBr pellets (BIO-RAD FTS-3000). 

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