Characterization of an MIR-LED as an excitation source for photoacoustic sensing of N2O

Abstract

Nitrous oxide (N2O) is an extremely effective greenhouse gas emitted in large quantities from agriculturally used soils. Traditional methodologies to monitor this gas are typically associated with significant costs. In this study, we report on the characterization of a low-cost MIR-LED with spectral emission centered at 4.5 μm, to be used as excitation source in photoacoustic detection of nitrous oxide (N2O). N2O is emitted, in agriculture, in trace levels. Preliminary results suggest that the low power and divergence of the LED poses a significant challenge in the development of a LED based PA sensor, and that further developments on the PA cell are required to allow a better assessment of the feasibility of this light source to monitor N2O in agricultural sites.