The opposing effect of butanol and butyric acid on the abundance of bromide and iodide at the aqueous solution–air interface

• DOI: 10.1039/c8cp07448h
• Publication Date: 2019-04-04T09:25:51Z
• Authors: Ming-Tao Lee; Fabrizio Orlando; Morteza Khabiri; Martina Roeselová; Matthew A. Brown; Markus Ammann
• Keywords: 13. Climate action; 01 natural sciences; 0104 chemical sciences

The efficient oxidation of iodide and bromide at the aqueous solution-air interface ocean or sea spray aerosol particles had been suggested to be related their surface propensity. ubiquitous presence organic material calls for an assessment impact often surface-active compounds on interfacial density halide ions. We used in situ X-ray photoelectron spectroscopy with a liquid micro-jet obtain chemical composition information solution-vapor interfaces from mixed solutions containing 1-butanol butyric acid as surfactants. Core level spectra Br 3d, Na 2s, C 1s O ca. 160 eV kinetic energy core I 4d 400 are compared function concentration. A simple model was developed account attenuation photoelectrons by aliphatic carbon layer surfactants changing local response observed that increases 25%, while reduces it 40%, both comparison pure solution. Qualitatively similar behavior case iodide. Classical molecular dynamics simulations failed reproduce details ions two organics. This is attributed lack correct monovalent ion parameters low concentration possibly leading overestimation absence results clearly demonstrate change electrostatic interactions near headgroup specific effects. has implications halogen activation processes specifically when oxidants interact particles.