Figure-of-Merit Characterization of Hydrogen-Bond Acidic Sorbents for Waveguide-Enhanced Raman Spectroscopy
Nathan F Tyndall1, Todd H Stievater1, Dmitry A Kozak1
1Naval Research Laboratory, Washington 20375, District of Columbia, United States.
ACS Sensors
|March 11, 2020
Summary
This study evaluates sorbent materials for waveguide-enhanced Raman spectroscopy (WERS) of organophosphonates. A new figure-of-merit helps assess sorbent quality for improved chemical sensing applications.
Area of Science:
- Analytical Chemistry
- Materials Science
- Spectroscopy
Background:
- Waveguide-enhanced Raman spectroscopy (WERS) requires specific sorbent material properties for effective vapor-phase analysis.
- Organophosphonates are a class of chemicals requiring sensitive detection methods.
Purpose of the Study:
- To evaluate the in situ optical properties of hydrogen-bond acidic sorbent materials for WERS.
- To assess sorbent suitability for detecting vapor-phase organophosphonates.
- To develop a quantitative framework for evaluating new sorbent materials.
Main Methods:
- In situ evaluation of sorbent optical properties.
- Measurement of infrared absorption and Raman spectral background.
- Determination of the limit of detection for dimethyl methylphosphonate (DMMP).
- Correlation of chemical properties with optical performance.
Main Results:
- Sorbent materials exhibit varying optical properties critical for WERS.
- Infrared absorption, Raman background, and DMMP detection limits differ significantly among sorbents.
- Chemical properties directly influence the optical performance of sorbents for sensing.
Conclusions:
- A sorbent figure-of-merit was introduced to quantify performance differences.
- This figure-of-merit provides a framework for assessing and developing new sorbent materials for WERS.
- The findings facilitate improved sensing of organophosphonates.
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