QEPAS for chemical analysis of multi-component gas mixtures

A gas sensor based on quartz-enhanced photoacoustic spectroscopy and using near-infrared, fiber-coupled diode lasers as an excitation source was developed for chemical analysis of gas mixtures containing H2S, CO2, and CH4 at concentrations from 0 to 100%. Analysis of physical phenomena affecting the sensor operation is performed, the sensor performance is evaluated, and simple algorithms are developed to derive concentrations of the gases from detected electrical signals.