Unformatted text preview: m temperature
and shaken vigorously in an attempt to break up any lumps of
material and obtain a uniform mixture of any unreacted
constituents then placed back into the oven for the remaining
4 - 8 d ay intercalation period. The final step in the preparation of the intercalated
samples was to drop quench the ampoules (from 800 C - g roup A a nd 1 000 C - g roup B ) by dropping them into a beaker of cold
tap water. The samples were then screened using a stainless steel sc'reen having 200 u m. holes to separate any remaining
lumps of material before being tested.
The resulting powders were in the form of hexagonal
platelets having a typical size in the range. of 5 - 1 5 u m. x
1 - 3 u m . thick as determined from pictures taken using a scanning electron microscope. X-ray Fluorescence and X-ray data were then taken to verify the integrity and composition
of the samples. P age - 23- C HAPTER 3
Sample Characterization 3-1 (a) XRF Sample Verification
(GROUP A - q uenched from 800 C) X -ray fluorescence (XRF) spectra were obtained from of
the A gxTiS2 p owder samples which were quench cooled f rom
8 0 0 C (group A ) a s a check of the ratio of Ag to T iS2. A S IEMENS KRISTALLOFLEX 2 X -ray generator was used to generate
Z n K a ( 8.631 Kev.) and Z n K b ( 9 . 5 7 2 Kev.) X-rays. The energies of the emitted X-rays are characteristic of the element.
The various (group A) powder samples ( 0 < x < 0 . 6 ) were
placed on a polyester film ( < 4 u m. thick) over the incident
Z n X-rays. A KEVEX-RAY 0800 S i(Li) d etector located 2 c m . from the sample perpendicular to the incident X-rays was used
to detect the intensities of the fluorescent X-rays emitted
from the sample. The data was collected using a NUCLEAR DATA ND-66 multi-channel analyzer with windows set up around the
a nd silver L peaks. The intensities
o f the respective peaks are directly related to the weight
sulfur K concentration of the element in the sample.
Intensity ratios of S /Ti a nd A g/Ti w ere calculated from
the intensity mea...
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- Fall '09
- Diffraction, Sulfur, Intercalation, lattice parameters