A novel heterogeneous reaction for generating gaseous nitrous acid

The short-lived reactive specimen nitrous acid HONO was generated in the gas phase by the heterogeneous reaction of gaseous HCl with AgNO2 which can generate higher concentration of HONO than other methods. We investigated the process from generation to dissociation in the gas phase under different controlled temperatures, and discussed the ionization and reaction on the solid surface by com-bination of the photoelectron spectroscopy and photoionization mass spectroscopy (PES-PIMS) and in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS).