Uptake coefficient of H2O2 on ice

Abstract

H2O2 uptake coefficients on ice surfaces, over a temperature range from 190 to 220 K, have been studied in a flow reactor coupled with a differentially pumped quadrupole mass spectrometer. The initial uptake coefficient increases with an increase in H2O2 pressure and a decrease in temperature. The results were analyzed using surface kinetics, and the analysis shows that the uptake involves both H2O2 adsorption and surface aggregation. H2O2 desorption kinetics supports lateral attractive interactions among adsorbed H2O2 on ice. The result can be used to model the heterogeneous H2O2 loss on snow/ice surfaces and cirrus clouds as a function of the H2O2 concentration and temperature