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Title: Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell

Abstract

We describe a versatile mid-infrared (Mid-IR) spectroscopy system developed to measure the concentration of a wide range of gases with an ultra-low sample size. The system combines a rapidly-swept external cavity quantum cascade laser (ECQCL) with a hollow fiber gas cell. The ECQCL has sufficient spectral resolution and reproducibility to measure gases with narrow features (e.g., water, methane, ammonia, etc.), and also the spectral tuning range needed to measure volatile organic compounds (VOCs), (e.g., aldehydes, ketones, hydrocarbons), sulfur compounds, chlorine compounds, etc. The hollow fiber is a capillary tube having an internal reflective coating optimized for transmitting the Mid-IR laser beam to a detector. Sample gas introduced into the fiber (e.g., internal volume = 0.6 ml) interacts strongly with the laser beam, and despite relatively modest path lengths (e.g., L ~ 3 m), the requisite quantity of sample needed for sensitive measurements can be significantly less than what is required using conventional IR laser spectroscopy systems. Example measurements are presented including quantification of VOCs relevant for human breath analysis with a sensitivity of ~2 picomoles at a 1 Hz data rate.

Authors:
; ; ; ; ; ;
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1358510
Report Number(s):
PNNL-SA-125504
453060031
DOE Contract Number:
AC05-76RL01830
Resource Type:
Conference
Resource Relation:
Conference: Next-Generation Spectroscopic Technologies X, April 9, 2017, Anaheim, California. Proceedings of the SPIE, 10210:Article No. 1021003
Country of Publication:
United States
Language:
English
Subject:
spectroscopy; broad-tuning; ECQCL; c

Citation Formats

Kriesel, Jason M., Makarem, Camille N., Phillips, Mark C., Moran, James J., Coleman, Max, Christensen, Lance, and Kelly, James F. Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell. United States: N. p., 2017. Web. doi:10.1117/12.2262612.
Kriesel, Jason M., Makarem, Camille N., Phillips, Mark C., Moran, James J., Coleman, Max, Christensen, Lance, & Kelly, James F. Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell. United States. doi:10.1117/12.2262612.
Kriesel, Jason M., Makarem, Camille N., Phillips, Mark C., Moran, James J., Coleman, Max, Christensen, Lance, and Kelly, James F. Fri . "Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell". United States. doi:10.1117/12.2262612.
@article{osti_1358510,
title = {Versatile, ultra-low sample volume gas analyzer using a rapid, broad-tuning ECQCL and a hollow fiber gas cell},
author = {Kriesel, Jason M. and Makarem, Camille N. and Phillips, Mark C. and Moran, James J. and Coleman, Max and Christensen, Lance and Kelly, James F.},
abstractNote = {We describe a versatile mid-infrared (Mid-IR) spectroscopy system developed to measure the concentration of a wide range of gases with an ultra-low sample size. The system combines a rapidly-swept external cavity quantum cascade laser (ECQCL) with a hollow fiber gas cell. The ECQCL has sufficient spectral resolution and reproducibility to measure gases with narrow features (e.g., water, methane, ammonia, etc.), and also the spectral tuning range needed to measure volatile organic compounds (VOCs), (e.g., aldehydes, ketones, hydrocarbons), sulfur compounds, chlorine compounds, etc. The hollow fiber is a capillary tube having an internal reflective coating optimized for transmitting the Mid-IR laser beam to a detector. Sample gas introduced into the fiber (e.g., internal volume = 0.6 ml) interacts strongly with the laser beam, and despite relatively modest path lengths (e.g., L ~ 3 m), the requisite quantity of sample needed for sensitive measurements can be significantly less than what is required using conventional IR laser spectroscopy systems. Example measurements are presented including quantification of VOCs relevant for human breath analysis with a sensitivity of ~2 picomoles at a 1 Hz data rate.},
doi = {10.1117/12.2262612},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Fri May 05 00:00:00 EDT 2017},
month = {Fri May 05 00:00:00 EDT 2017}
}

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