Mass spectroscopy surface-enhanced laser

Techniques that have been applied include time of flight static secondary ion mass spectrometry (SSIMS)/ " low energy ion scattering spectromehy, x-ray photoelectron microscopy scanning electrochemical microscopy (SECM), laser ionization mass spectrometry, surface enhanced infrared reflection spectroscopy, Fourier Transform infrared spechoscopy and nuclear magnetic resonance spectroscopy. ... 

To understand better the complicated electrochemical behavior of solid fullerenes, numerous complementary techniques have been used. These include SECM, EQCM, laser desorption mass spectrometry, surface enhanced Raman spectroscopy, electron paramagnetic resonance, spectroelectrochemical techniques, optical microscopy, conductivity measurements, SEM, and X-ray diffraction. The results of these studies are summarized below. 

There are several MS-based techniques that can provide chemical information for thin and thick layers [12]. For very thin layers (sub to 1-2 monolayers), nondestructive techniques such as static SIMS [13], ion scattering MS [14], or MS of recoiled ions [15] are suitable. These techniques are also the best adapted for examining surface contamination. They are all based on surface interactions of an ion beam with the solid surface. For depth profiling of thin and thick layers, MS is associated with a destructive source of neutrals or ions dynamic SIMS, secondary neutron mass spectroscopy (SNMS), glow discharge mass spectroscopy (GD-MS), matrix-enhanced SIMS, laser desorption/ionization MS, and desorption electrospray ionization (DESI) MS [16]. Ions are either desorbed from the solid surface or generated by postionization of neutrals sputtered off the surface. 

Tunable laser spectroscopic techniques such as laser-induced fluorescence (LIF) or resonantly enhanced multi-photon ionization (REMPI) are well-established mature fields in gas-phase spectroscopy and dynamics, and their application to gas-surface dynamics parallels their use elsewhere. The advantage of these techniques is that they can provide exceedingly sensitive detection, perhaps more so than mass spectrometers. In addition, they are detectors of individual quantum states and hence can measure nascent internal state population distributions produced via the gas-surface dynamics. The disadvantage of these techniques is that they are not completely general. Only some interesting molecules have spectroscopy amenable to be detected sensitively in this fashion, e.g., H2, N2, NO, CO, etc. Other interesting molecules, e.g. 02, CH4, etc., do not have suitable spectroscopy. However, when applicable, the laser spectroscopic techniques are very powerful. 

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