Surface enhanced absorption

Phenomena such as quantum dots, fluorescent nano clusters, REF (resonance enhanced fluorescence), SERS (surface enhanced Raman-spectroscopy), SEA (surface enhanced absorption), or unique catalytic effects are the major technological quantum leaps of nano technology. 

SERRS Surface-enhanced RRS [214, 217] Same as SERS but using a wavelength corresponding to an absorption band Magnetic Spectroscopies Same as SERS... 

Muiier C, Machtie P and Heim C A 1994 Enhanced absorption within a cavity. A study of thin dye iayers with the surface forces apparatus J. Rhys. Chem. 98 11 119-25... 

Kerker, M. and Blatehford, C.G. (1982) Elastic scattering, absorption, and surface-enhanced Raman scattering by concentric spheres comprised of a metaUic and a dielectric region. Physical Remeu> B — Condensed Matter, 26, 4052—4063. 

Osawa, M Tsushima, M Mogami, H., Samjeske, G. and Yamakata, A. (2008) Structure of water at the electrified platinum-water interface a study by surface-enhanced infrared absorption spectroscopy. J. Phys. Chem. C, 112, 4248- 256. 

Yamakata, A., Uchida, T., Kubota, J. and Osawa, M. (2006) Laser-induced potential jump at the electrochemical interface probed by picosecond time-resolved surface-enhanced infrared absorption spectroscopy./. Phys. Chem. B, 110, 6423-6427. 

Figure 6.16 Attenuated total reflection surface enhanced infrared reflection absorption spectroscopy (ATR-SEIRAS) spectra for the oxidation of 0.1 M HCOOH in 0.5 M H2SO4 on a polycrystaUine electrode. The bands at 2055 -2075 and 1800-1850 cm are assigned to linear- and bridge-bonded CO, whereas the band at 1323 cm corresponds to adsorbed formate. (Reproduced from Samjeske et al. [2006].)...

Samjeske G, Miki A, Ye S, Osawa M. 2006. Mechanistic study of electrocatal3dic oxidation of formic acid at platinum in acidic solution by time-resolved surface-enhanced infrared absorption spectroscopy. J Phys Chem B 110 16559-16566. 

Watanabe M, Zhu Y, Uchida H. 2000. Oxidation of CO on a Pt-Fe alloy electrode studied by surface enhanced infrared reflection-absorption spectroscopy. J Phys Chem B 104 1762-1768. 

Miki A, Ye S, Osawa M. 2002. Surface-enhanced IR absorption on platinum nanoparticles an apphcation to real-time moititoring of electrocatalytic reactions. Chem Commun (14) 1500-1501. 

Sun SG, Cai WB, Wan LJ, Osawa M. 1999. Infrared absorption enhancement for CO adsorbed on Au films in perchloric acid solutions and effects of surface structure studied by cyclic voltammetry, scanning tunneling microscopy, and surface-enhanced IR spectroscopy. J Phys Chem B 103 2460-2466. 

LC-IR using surface-enhanced IR absorption spectroscopy (SEIRAS) was recently designed in order to develop a highly sensitive and rapid analysis method for polymer additives [506]. The method, which consists of spraying the LC eluents on to a metal film of Ag on a BaF2 substrate, allows an enhancement factor of about 90. 

A related effect has been described for IR spectroscopy - Surface Enhanced Infrared Absorption spectroscopy (SEIRA). However, as the enhancement factors are significantly lower than for SERS and both the required metal particle size and the activation distance between the target molecule and the particle are more than one order of magnitude smaller, no practically applicable SEIRA sensors have been demonstrated up to now. 

In contrast to Raman scattering, the absorption of infrared (IR) radiation is a first-order process, and in principle a surface or an interface can generate a sufficiently strong signal to yield good IR spectra [6]. However, most solvents, in particular water, absorb strongly in the infrared. There is no special surface enhancement effect, and the signal from the interface must be separated from that of the bulk of the solution. 

The broadband analysis was confirmed by the experimental results mentioned in Sect. 5.4.1. This method can also be further enhanced by some of the techniques described in Sects. 5.4.2 and 5.4.3. The conclusion is that these methods of microcavity-enhanced optical absorption sensing provide compact, inexpensive, and sensitive detectors for molecular species in the ambient gas or liquid, and that further increases in sensitivity can be implemented to make them even more competitive. The molecular-transition specificity that is implicit in absorption spectroscopy is a limiting restriction, but the surface-enhanced Raman sensing that is enabled by metallic nanoparticles on the microresonator surface can significantly increase the number of molecular species that could be detected. 

Osawa, M., Surface enhanced infrared absorption, In Near Field Optics and Plasmon Polar itons Kawata, S., Ed. Springer, Berlin, 2001, 163 187... 

Some characteristics of, and comparisons between, surface-enhanced Raman spectroscopy (SERS) and infrared reflection-absorption spectroscopy (IRRAS) for examining reactive as well as stable electrochemical adsorbates are illustrated by means of selected recent results from our laboratory. The differences in vibrational selection rules for surface Raman and infrared spectroscopy are discussed for the case of azide adsorbed on silver, and used to distinguish between "flat" and "end-on" surface orientations. Vibrational band intensity-coverage relationships are briefly considered for some other systems that are unlikely to involve coverage-induced reorientation. 

The combination of surface enhanced Raman scattering (SERS) and infrared reflection absorption spectroscopy (IRRAS) provides an effective in-situ approach for studying the electrode-electrolyte interface. The extreme sensitivity to surface species of SERS is well known. By using polarization modulation of the infrared beam for IRRAS, the complete band shape is obtained without modulating the electrode potential. 

Surface-enhanced resonance Raman scattering (SERRS), 21 327-328 advantage of, 21 329 Surface Evolver software, 12 11 Surface excess, 24 135, 136 Surface extended X-ray absorption fine structure (SEXAFS), 19 179 24 72 Surface filtration, 11 322-323 Surface finish(es). See also Electroplating in electrochemical machining, 9 591 fatigue performance and, 13 486-487 Surface finishing agents, 12 33 Surface force apparatus, 1 517 Surface force-pore flow (SFPF) model,... 

In addition to the indirect experimental evidence coming from work function measurements, information about water orientation at metal surfaces is beginning to emerge from recent applications of a number of in situ vibrational spectroscopic techniques. Infrared reflection-absorption spectroscopy, surface-enhanced Raman scattering, and second harmonic generation have been used to investigate the structure of water at different metal surfaces, but the pictures emerging from all these studies are not always consistent, partially because of surface modification and chemical adsorption, which complicate the analysis. 

Cation radicals of several metallated TPP and OEP complexes were reported to have unique IR active ring modes (21. These absorptions were observed in the region 1250-1290 cm for TPP complexes and 1520-1570 cm for OEP complexes. IR and raman active modes have also been observed for several different reduced oxygen species adsorbed on various metal substrates. Observations of the adsorption of oxygen on silver by surface enhanced raman spectroscopy (SERS) 22), show superoxide molecules (O2) have a frequency of 1053 cm, and peroxide (0 ) of 697 cm. This same study reported additional peaks were observed at 815 cm and 1286... 

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