CH4/C2H6 dual gas sensing system using a single mid-infrared laser

Jiachen Sun; Jun Chang; Yu Zhang; Yubin Wei; Qinduan Zhang; Fupeng Wang; Shan Lin; Zihan Wang; Minghui Mao

doi:10.1016/j.saa.2023.122368

CH₄/C₂H₆ dual gas sensing system using a single mid-infrared laser

Spectrochim Acta A Mol Biomol Spectrosc. 2023 Apr 15:291:122368. doi: 10.1016/j.saa.2023.122368. Epub 2023 Jan 13.

Authors

Jiachen Sun¹, Jun Chang², Yu Zhang³, Yubin Wei³, Qinduan Zhang³, Fupeng Wang⁴, Shan Lin⁵, Zihan Wang¹, Minghui Mao⁵

Affiliations

¹ School of Information Science and Engineering, and Shandong Provincial Key Laboratory of Laser Technology and Application, Shandong University, 72 Binhai Road, Qingdao 266237, China.
² School of Information Science and Engineering, and Shandong Provincial Key Laboratory of Laser Technology and Application, Shandong University, 72 Binhai Road, Qingdao 266237, China. Electronic address: changjun@sdu.edu.cn.
³ Laser Institute, Qilu University of Technology (Shandong Academy of Sciences), Jinan 250102 China.
⁴ College of Information Science and Engineering, Ocean University of China, Qingdao 266100, China.
⁵ Key Laboratory of Education Ministry for Laser and Infrared System Integration Technology, Shandong University, 72 Binhai Road, Qingdao 266237, China.

PMID: 36657290
DOI: 10.1016/j.saa.2023.122368

Abstract

Methane (CH₄) and ethane (C₂H₆) dual gas sensor with low system complexity and strong stability is proposed. The correction method based on absorbance spectrum is applied, and the cross-interference of C₂H₆ to CH₄ is eliminated. In the single gas concentration measurement, linear fitting is performed between the absorbance and concentration of CH₄ and C₂H₆, and the correlation coefficients of R² = 0.99959 and R² = 0.99994 are obtained respectively, which proves that the accuracy of the dual gas sensor is robust. In the dual gas concentration measurement, we carry out continuous measurement of five mixed gases and a long-term measurement of a mixture of gases, which verifies that our sensor has the fast response speed and strong stability. The minimum detectable column densities of 0.62 ppm·m for CH₄ and 0.1 ppm·m for C₂H₆ are achieved, respectively. The CH₄/C₂H₆ dual gas sensor assisted by the correction method has high sensitivity and strong robustness to cross-interference, and has great potential for application in various scenarios.

Keywords: Correction method; Cross-interference; Direct absorption spectroscopy; Dual gas sensor.