A three-channel thermal dissociation cavity ring-down spectrometer for simultaneous measurement of ambient total peroxy nitrates, total alkyl nitrates, and NO2

Chuan Lin; Renzhi Hu; Pinhua Xie; Guoxian Zhang; Xiaoyan Liu; Jinzhao Tong; Wenqing Liu

doi:10.1016/j.talanta.2023.125524

A three-channel thermal dissociation cavity ring-down spectrometer for simultaneous measurement of ambient total peroxy nitrates, total alkyl nitrates, and NO₂

Talanta. 2024 Apr 1:270:125524. doi: 10.1016/j.talanta.2023.125524. Epub 2023 Dec 8.

Authors

Chuan Lin¹, Renzhi Hu², Pinhua Xie³, Guoxian Zhang⁴, Xiaoyan Liu⁵, Jinzhao Tong⁶, Wenqing Liu⁴

Affiliations

¹ Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China; University of Science and Technology of China, Hefei, 230027, China.
² Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China. Electronic address: rzhu@aiofm.ac.cn.
³ Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China; University of Science and Technology of China, Hefei, 230027, China; University of Chinese Academy of Sciences, Beijing, 100049, China. Electronic address: phxie@aiofm.ac.cn.
⁴ Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China.
⁵ College of Pharmacy, Anhui Medical University, Hefei, 230032, China.
⁶ University of Science and Technology of China, Hefei, 230027, China.

PMID: 38128285
DOI: 10.1016/j.talanta.2023.125524

Abstract

A newly constructed thermal dissociation cavity ring-down spectrometer (TD-CRDS) for the simultaneous measurement of ambient total peroxy nitrates (ΣPNs, RO₂NO₂), total alkyl nitrates (ΣANs, RONO₂), and NO₂ was presented in this work. ΣPNs and ΣANs were detected as NO₂ with the CRDS instrument after thermal dissociation. PNs and ANs completely dissociated at 180 °C and 360 °C, with conversion efficiencies of 96 % and 99 %, respectively. The effects of NO₂ and NO on measurement in different temperatures and two types of thermal dissociation inlet (TDI) were further explored. The influence of ambient NO₂ and NO on PNs and ANs in the improved TDI (TDI-2) was significantly improved. To further enhance the measurement accuracy, the consistency of the observed NO₂ in the three channels was tested, which achieved good agreement. The detection limits of the TD-CRDS instrument for NO₂, ΣPNs, and ΣANs were determined as 6.5, 6.8, and 8.6 pptv (10 s, 1σ), respectively. Observations of PNs and ANs were conducted in a suburban site in Hefei, China, from September 2-30, 2021, using the TD-CRDS instrument, and the consecutive time series of PNs and ANs were derived, verifying the capability of the TD-CRDS instrument for continuous field observations of ΣPNs and ΣANs.

Keywords: Gas monitoring; Optical detection devices; Thermal dissociation cavity ring-down spectroscopy (TD-CRDS); Total alkyl nitrates (ΣANs); Total peroxy nitrates (ΣPNs).