Precise temperature control and rapid heating/cooling of infrared spectroscopy samples with a two-stage thermoelectric device

Abstract

The design and performance of an apparatus for heating and cooling samples during variable temperature infrared spectroscopy studies are described.

A Temperature Perturbation Infrared Spectroscopy Comparison of HY and NaY Zeolite Dehydration/Rehydration

“…The apparatus and methodologies employed for temperature step infrared spectrum measurements are described in detail elsewhere [30,34]. The infrared spectrophotometer was purged with dry air to reduce spectral artifacts caused by fluctuations in water vapor concentration.…”

“…0.3% RH during infrared spectrum measurements. Previous benchmark studies revealed the importance of good thermal contact between solid samples and the bottom of the button sample holder to achieve accurate temperature measurements [30]. For this reason, samples were deposited in the button sample holder as water slurries.…”

“…Findings from the variabletemperature X-ray and infrared spectroscopy studies of NaY are augmented by results obtained from the temperature perturbation infrared spectroscopy studies of HY and NaY described here. By using a unique sample heating and cooling apparatus [30], subtle infrared spectrum changes caused by heating and cooling HY and NaY were compared. By rapidly (i.e., 2 • C s −1 ) heating and cooling samples to pre-selected temperatures prior to isothermal spectrum measurements, vibrational band changes associated with loss or gain of small quantities of water were distinguished from those attributed to the thermal expansion and contraction of the crystalline zeolite.…”