Surface analysis Essay Example | Topics and Well Written Essays - 2000 words

Surface analysis - Essay ExampleFor example, corrosion in metal is prevented through the use of specific chemicals various optical do on lenses may be done through special coatings and automobile emissions are significantly reduced through the unique chemical composition on the surface of an auto-exhaust catalyst. To achieve the desired function, the surface a material should be analyzed to determine its physical characteristics, chemical composition, chemical and atomic structure, electronic state, and molecular bonding (Vickerman, 2009). Methods Several proves may be applied on a solid surface to measure its response, namely electrons, ions, neutrons, photons, and heat or field. Each probe has a specific response. The combination of probes and corresponding responses provides 36 basic classes of experimental techniques which may be utilized for surface analysis. Table 1 Most commonly Used Surface Analysis Methods Incident Excitation Probe photon electron ion neutron electric/ma gnetic field Radiation Detected photon FTIR, Raman, XAFS, EXAFS, SFG, IR EDAX NRA GDOES electron XPS/ESCA, UPS, (AE) XAFS AES, surface-to-air missile, SEM, TEM, LEED, RHEED, SPE, STM, EELS STM, AFM ion SIMS, LEIS, RBS, ISS neutron INS As shown in Table 1, the following shows the most commonly used surface analysis methods FTIR Fourier Transform Infrared spectrometry Raman Vibrational spectrographic analysis XAFS X-ray ducking Fine Structure analysis EXAFS Extended X-ray Absorption Fine Structure analysis SFG Sum Frequency Generation IR Infrared Spectroscopy EDAX cypher Dispersive Analysis of X-rays NRA Nuclear Reaction Analysis GDOES Glow Discharge Optical Emission Spectroscopy XPS/ESCA X-ray Photoelectron Spectroscopy / Electron Spectroscopy for Chemical Analysis UPS Ultraviolet Photoelectron Spectroscopy (AE) XAFS Auger Emission X-ray Absorption Fine Structure analysis AES Auger Electron Spectroscopy SAM Scanning Auger Spectroscopy SEM Scanning Electron Microscopy TEM Transmission Electron Microscopy LEED Low Energy Electron Diffraction RHEED Reflection High Energy Electron Diffraction SPE crack Polarized Electron spectroscopy STM Scanning Tunnelling Microscopy EELS Electron Energy Loss Spectroscopy AFM Atomic Force Microscopy SIMS Secondary Ion Mass Spectrometry LEIS Low Energy Ion Scattering spectroscopy RBS Rutherford Backscattering Spectroscopy ISS Ion Scattering Spectroscopy and INS Inelastic Neutron Scattering Analysis Auger electron spectroscopy or AES is considered as a key out chemical surface analysis tool for conducting material samples. The AES technique is based on the excitation of auger electrons which allow not only the imaging of atoms precisely for chemical identification as well. Information available through AES ranges between the first 2 to 10 atomic layers of the sample surface (Matheiu, 2009). Meanwhile, low zipper electron diffraction or LEED works by bombarding a surface with beam of low energy electr ons which enable the identification of the surface structure by electron diffraction (Vickerman, 2009). A beam of low energy electrons between 10 to 200 eV is used to determine crystallographic structure. A device called a Retarding Field analyzer is utilized to detect diffracted electrons. Diffracted electrons appear as spots on a phosphorescent screen which move according to energy variations of electrons. The intensity of the spots to a fault provides information regarding surface reconstructions (Walker, 2011). An auger