Counterintuitive Oxidation of Alcohols at Air-Water Interfaces.
J Am Chem Soc
; 145(8): 4791-4799, 2023 Mar 01.
Article
em En
| MEDLINE
| ID: mdl-36795890
ABSTRACT
This study shows that the oxidation of alcohols can rapidly occur at air-water interfaces. It was found that methanediols (HOCH2OH) orient at air-water interfaces with a H atom of the -CH2- group pointing toward the gaseous phase. Counterintuitively, gaseous hydroxyl radicals do not prefer to attack the exposed -CH2- group but the -OH group that forms hydrogen bonds with water molecules at the surface via a water-promoted mechanism, leading to the formation of formic acids. Compared with gaseous oxidation, the water-promoted mechanism at the air-water interface significantly lowers free-energy barriers from â¼10.7 to â¼4.3 kcal·mol-1 and therefore accelerates the formation of formic acids. The study unveils a previously overlooked source of environmental organic acids that are bound up with aerosol formation and water acidity.
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MEDLINE
Idioma:
En
Ano de publicação:
2023
Tipo de documento:
Article