A new method for measuring ambient 1,3-butadiene through active DOAS

As one of highly reactive dialkenes, 1,3-butadiene (BD) plays a significant role in the atmospheric radical cycle. We have introduced a novel method for the online measurement of ambient BD using the Differential Optical Absorption Spectroscopy (DOAS) technique. During lab testing, the correlation coefficient (R2) between measured BD concentrations and standard concentrations consistently exceeded 0.9999. The accuracy and precision were within ± 5% and 1%, respectively. Interference testing demonstrated that DOAS can effectively distinguish between substances and accurately fit BD concentrations. Following field measurement, the detection limit for BD reached 90 pptv, the R2 between DOAS and the online VOCs system results reaches 0.85, with a slope of 0.86. With its minute-level temporal resolution and cost-effectiveness, DOAS is suitable for long-term BD measurements and has been further validated as an effective method to provide valuable data support for in-depth investigations into the atmospheric oxidation processes of BD.This work was supported by Sino-German Mobility Program (M-0509) and National Natural Science Foundation of China (grant number 42075097, 22176037, 42375089, 22376030).