nerc.ac.uk

Uptake of Gaseous Hydrogen Peroxide by Submicrometer Titanium Dioxide Aerosol as a Function of Relative Humidity

Pradhan, Manik; Kalberer, Markus; Griffiths, Paul T.; Braban, Christine F.; Pope, Francis D.; Cox, R. Anthony; Lambert, Richard M.. 2010 Uptake of Gaseous Hydrogen Peroxide by Submicrometer Titanium Dioxide Aerosol as a Function of Relative Humidity. Environmental Science & Technology, 44 (4). 1360-1365. 10.1021/es902916f

Full text not available from this repository.

Abstract/Summary

Hydrogen peroxide (H2O2) is an important atmospheric oxidant that can serve as a sensitive indicator for HOx (OH + HO2) chemistry. We report the first direct experimental determination of the uptake coefficient for the heterogeneous reaction of gas-phase hydrogen peroxide (H2O2) with titanium dioxide (TiO2), an important component of atmospheric mineral dust aerosol particles. The kinetics of H2O2 uptake on TiO2 surfaces were investigated using an entrained aerosol flow tube (AFT) coupled with a chemical ionization mass spectrometer (CIMS). Uptake coefficients (γH2O2) were measured as a function of relative humidity (RH) and ranged from 1.53 × 10−3 at 15% RH to 5.04 × 10−4 at 70% RH. The observed negative correlation of RH with γH2O2 suggests that gaseous water competes with gaseous H2O2 for adsorption sites on the TiO2 surface. These results imply that water vapor plays a major role in the heterogeneous loss of H2O2 to submicrometer TiO2 aerosol. The results are compared with related experimental observations and assessed in terms of their potential impact on atmospheric modeling studies of mineral dust and its effect on the heterogeneous chemistry in the atmosphere.

Item Type: Publication - Article
Digital Object Identifier (DOI): 10.1021/es902916f
Programmes: CEH Topics & Objectives 2009 - 2012 > Biogeochemistry
CEH Programmes pre-2009 publications > Biogeochemistry > BG01 Measuring and modelling trace gas, aerosol and carbon
CEH Sections: Billett (to 30 Nov 2013)
ISSN: 0013-936X
NORA Subject Terms: Atmospheric Sciences
Date made live: 19 Apr 2010 10:02
URI: http://nora.nerc.ac.uk/id/eprint/7618

Actions (login required)

View Item View Item