Influence of different solar spectra on the products of photochemical interactions at the air/water interface

Photochemical interactions at the air/water interface under atmospheric circumstances are strongly affected by the atmospheric conditions, e.g. temperature, humidity, and solar spectrum. The rate and mechanism of photochemical interactions at such interfaces are impacted by the presence of photosensitizers and the spectral distribution of solar irradiation. This influences the climate balance by controlling the volatile organic compounds (VOCs) emitted to the atmosphere. Despite numerous investigations on the emission and uptake of gases and aerosols into the atmosphere, there is still a lack in our knowledge about the particular effect of different solar irradiations corresponding to different time, altitude, latitude and longitude of the earth. We utilized our recently developed LED-based solar simulator that was designed specifically for this purpose. The interaction products were detected using mass spectrometry. In this presentation, we will show the influence of different irradiation spectra on the photosensitized chemistry of nonanoic acid, as a fatty acid, at the air/water Interface in the presence of 4-benzoylbenzoic acid, as a photosensitizer. We found different generations of organic acids in the liquid phase and aromatic compounds in the gas phase upon irradiation with different spectral distributions. We will compare our findings with those published by Tinel et al., (2016) on the same system, however using a Xenon lamp (150 W Xe) as an irradiation source.