A dual-gas sensor for simultaneous detection of methane and acetylene based on time-sharing scanning assisted wavelength modulation spectroscopy

Lewen Zhang; Zhirong Zhang; Pengshuai Sun; Tao Pang; Hua Xia; Xiaojuan Cui; Qiang Guo; Markus Werner Sigrist; Chimin Shu; Zhifeng Shu

doi:10.1016/j.saa.2020.118495

A dual-gas sensor for simultaneous detection of methane and acetylene based on time-sharing scanning assisted wavelength modulation spectroscopy

Spectrochim Acta A Mol Biomol Spectrosc. 2020 Oct 5:239:118495. doi: 10.1016/j.saa.2020.118495. Epub 2020 May 16.

Authors

Lewen Zhang¹, Zhirong Zhang², Pengshuai Sun³, Tao Pang³, Hua Xia³, Xiaojuan Cui³, Qiang Guo⁴, Markus Werner Sigrist⁵, Chimin Shu⁶, Zhifeng Shu⁷

Affiliations

¹ Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China; University of Science and Technology of China, Hefei 230026, China.
² Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Key Lab of Environmental Optics & Technology, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Advanced Laser Technology Laboratory of Anhui Province, Hefei, Anhui 230037, China. Electronic address: zhangzr@aiofm.ac.cn.
³ Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
⁴ Anhui Provincial Key Laboratory of Photonic Devices and Materials, Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei, Anhui 230031, China; Advanced Laser Technology Laboratory of Anhui Province, Hefei, Anhui 230037, China.
⁵ Institute for Quantum Electronics, ETH Zurich, Otto-Stern-Weg 1, CH-8093 Zurich, Switzerland.
⁶ Department of Safety Health and Environmental Engineering, Yunlin University of Science and Technology, Taiwan 64002, China.
⁷ School of Physics and Materials Engineering, Hefei Normal University, Hefei, Anhui 230601, China.

PMID: 32470812
DOI: 10.1016/j.saa.2020.118495

Abstract

Methane (CH₄) and acetylene (C₂H₂) are important bioscience and chemical gases. The real-time monitoring and analysis of them have important research value in industrial process control. The time-sharing scanning assisted wavelength modulation spectroscopy (WMS) technique is developed for real-time and simultaneous detection of CH₄ and C₂H₂. This system involves two near-infrared distributed feedback (DFB) lasers and a compact multipass cavity with an effective optical path of 52.2 m. The selected strong absorption lines of methane and acetylene are located at 6046.96 cm-1 and 6531.7 cm-1, respectively. The experiment environment is conducted at room temperature 23 °C and pressure 760 Torr. The sensor performance, including the minimum detection limit (MDL) and the stability, was improved by eliminating the influence of light intensity fluctuation using the WMS-2f/SAW technique. Allan deviation analysis indicates that a MDL of 0.1 ppm for CH₄ and 0.2 ppm for C₂H₂ are achieved with 1-s integration time. And the instrument response time is about 44 s through the continuous analysis of standard gases. This sensitive, simple, reliable, and lowcost dual-gas sensor is very suitable for applications in the field environment, chemical process, and many other gas-phase analysis areas.

Keywords: Acetylene (C(2)H(2)); Allan deviation; Dual-gas sensor; Methane (CH(4)); Time-sharing scanning assisted wavelength modulation spectroscopy.