Abstract
In order to further improve the sensitivity of chemical IR sensors, research into a significant change in the signal generation mechanism was carried out. This effort was realized by generating the surface-enhanced IR absorption and Raman-scattering effect at silver- and gold-island-covered Ge- and ZnSe ATR surfaces for surface-enhanced infrared absorption (SEIRA) and Ag-layer-covered brass plates for surface-enhanced Raman scattering (SERS), respectively, and linking the optimized tools to the IR sensor concept. By careful optimization of the generation of silver-island and goldisland films on Ge reflection elements, intensity gains by a factor of 50 were achieved. Chemical interactions between the silver-island layer and the various analytes investigated up to now ( p -nitro benzoic acid, as a model compound, and selected aromatic and chlorinated pesticides) are likely, as indicated by significant IR spectral changes; the substances are, however, bound to the surfaces in a reversible manner. This property of the novel SEIRA sensor can be favorably exploited in flow-through systems. In a similar way, by a specially optimized treatment of anodically oxidized brass plates in a silver bath, repeatably usable SERS targets for the trace analysis of pesticide mixtures in aqueous systems could be developed. A signal enhancement factor of 1.4 million was obtained with pyridine as the standard sample. The data shown in this work suggest that both SEIRA and SERS can be coupled to a flow injection system in a reversible way for the molecular-specific trace analysis of organic compounds in aqueous solutions.
PDF Article
More Like This
RF sputtered amorphous chalcogenide thin films for surface enhanced infrared absorption spectroscopy
F. Verger, V. Nazabal, F. Colas, P. Němec, C. Cardinaud, E. Baudet, R. Chahal, E. Rinnert, K. Boukerma, I. Peron, S. Deputier, M. Guilloux-Viry, J.P. Guin, H. Lhermite, A. Moreac, C. Compère, and B. Bureau
Opt. Mater. Express 3(12) 2112-2131 (2013)
Cited By
You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.
Contact your librarian or system administrator
or
Login to access Optica Member Subscription