Nitrogen dioxide detection using tandem integrating spheres as a gas absorption cell based on gas absorption spectroscopy

Abstract

This paper presents a nitrogen dioxide detection device based on gas absorption spectroscopy by connecting two integrating spheres as a gas cell, observing the feasibility of the tandem integrating spheres as a gas cell, and taking a single integrating sphere as a gas cell for comparison experiments. Theoretical knowledge of the effective path length of tandem integrating spheres was established, and the theoretical derivation was further verified by experiments investigating the relationship between absorbance and gas concentration. This work makes it possible to develop a gas sensor that can reduce the volume of the gas cell and keep the effective optical path length unreduced.