Method for reducing the recovery time of gas sensors by photodissociation

Abstract

The invention relates to an LED-assisted photodissociation process for the controlled dissociation of gaseous molecules, particularly nitrogen dioxide (NO□). This process relies on the absorption of photons emitted by an LED at a specific wavelength, leading to the breaking of chemical bonds in the target molecules. In a vacuum environment, the LED light used has a peak intensity at 520 nm, corresponding to an energy of 2.37 eV. Although this value is lower than the dissociation energy of NO□ under normal atmospheric conditions (3.18 eV), the adapted experimental conditions allow for satisfactory results. The mechanism involved leads to the transformation of NO□ into nitric oxide (NO) and oxygen atoms according to the reaction: NO2 + hv -> NO + O.