Application Compendium - Agilent Technologies

Experimental
Instrumentation
To perform the analysis of micron-sized contaminants,
an Agilent Cary 660 FTIR spectrometer coupled to a
Cary 610 FTIR microscope was employed. In order to
facilitate direct measurement of the contaminated
regions, without any sample preparation, a ‘slide-on’
germanium micro attenuated total refl ectance (ATR)
accessory was used. The system enables fast, sensitive
and precise microscale direct measurements. The
accessory is also available with an optional diamond
crystal for the analysis of very hard materials.
Sample analysis
Minimal sample preparation was required for the
analysis. The contaminated regions were simply cut
out and placed on a glass slide, which was placed on
ATR
the sample stage of the Cary 610 FTIR microscope
coupled to a Cary 660 FTIR spectrometer. The system
was confi gured with standard mid-IR components
(mid-IR source, KBr beamsplitter, 250 micron narrow
band MCT microscope detector) with data collected
at 4 cm -1 spectral resolution with 32 co-added scans
(10 seconds).
Results and discussion
A section of the fuel tank cap (distinctive yellow in
color) that was free from contamination was sampled
by placing the ATR directly onto the sample surface.
High quality spectra were acquired in 10 seconds. The
contaminants (red specks) were visibly distinct from the
fuel cap, so data was collected from the center of one
of these sections. The resulting spectra are shown in
Figure 1.
Figure 1. ATR-FTIR analysis of a fuel tank cap. Top: Spectrum measured in a clean section; Bottom: Spectrum measured of a contaminated section
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