气候变化领域集成服务门户(CCPortal): Production of HONO from NO2 uptake on illuminated TiO2 aerosol particles and following the illumination of mixed TiO2ĝ•ammonium nitrate particles

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DOI	10.5194/acp-21-5755-2021
	Production of HONO from NO2 uptake on illuminated TiO2 aerosol particles and following the illumination of mixed TiO2ĝ•ammonium nitrate particles
	Dyson J.E.; Boustead G.A.; Fleming L.T.; Blitz M.; Stone D.; Arnold S.R.; Whalley L.K.; Heard D.E.
发表日期	2021
ISSN	1680-7316
起始页码	5755
结束页码	5775
卷号	21 期号:7
英文摘要	The rate of production of HONO from illuminated TiO2 aerosols in the presence of NO2 was measured using an aerosol flow tube system coupled to a photofragmentation laser-induced fluorescence detection apparatus. The reactive uptake coefficient of NO2 to form HONO, NO2!HONO, was determined for NO2 mixing ratios in the range 34 400 ppb, with NO2!HONO spanning the range (9.973.52) 10-6 to (1.260.17) 10-4 at a relative humidity of 151% and for a lamp photon flux of (1.630.09) 1016 photons cm-2 s-1 (integrated between 290 and 400 nm), which is similar to midday ambient actinic flux values. NO2!HONO increased as a function of NO2 mixing ratio at low NO2 before peaking at (1.260.17) 10-4 at 51 ppb NO2 and then sharply decreasing at higher NO2 mixing ratios rather than levelling off, which would be indicative of surface saturation. The dependence of HONO production on relative humidity was also investigated, with a peak in production of HONO from TiO2 aerosol surfaces found at 25% RH. Possible mechanisms consistent with the observed trends in both the HONO production and reactive uptake coefficient were investigated using a zero-dimensional kinetic box model. The modelling studies supported a mechanism for HONO production on the aerosol surface involving two molecules of NO2, as well as a surface HONO loss mechanism which is dependent upon NO2. In a separate experiment, significant production of HONO was observed from illumination of mixed nitrate=TiO2 aerosols in the absence of NO2. However, no production of HONO was seen from the illumination of nitrate aerosols alone. The rate of production of HONO observed from mixed nitrate=TiO2 aerosols was scaled to ambient conditions found at the Cape Verde Atmospheric Observatory (CVAO) in the remote tropical marine boundary layer. The rate of HONO production from aerosol particulate nitrate photolysis containing a photocatalyst was found to be similar to the missing HONO production rate necessary to reproduce observed concentrations of HONO at CVAO. These results provide evidence that particulate nitrate photolysis may have a significant impact on the production of HONO and hence NOx in the marine boundary layer where mixed aerosols containing nitrate and a photocatalytic species such as TiO2, as found in dust, are present. © 2021 BMJ Publishing Group. All rights reserved.
语种	英语
scopus关键词	aerosol; aerosol composition; ammonium; experimental study; nitrogen dioxide; nitrous acid; photodegradation; photolysis; reaction kinetics; saturation
来源期刊	ATMOSPHERIC CHEMISTRY AND PHYSICS
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/246972
作者单位	School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom; National Centre of Atmospheric Science, University of Leeds, Leeds, LS2 9JT, United Kingdom; School of Earth and Environment, University of Leeds, Leeds, LS2 9JT, United Kingdom
推荐引用方式 GB/T 7714	Dyson J.E.,Boustead G.A.,Fleming L.T.,等. Production of HONO from NO2 uptake on illuminated TiO2 aerosol particles and following the illumination of mixed TiO2ĝ•ammonium nitrate particles[J],2021,21(7).
APA	Dyson J.E..,Boustead G.A..,Fleming L.T..,Blitz M..,Stone D..,...&Heard D.E..(2021).Production of HONO from NO2 uptake on illuminated TiO2 aerosol particles and following the illumination of mixed TiO2ĝ•ammonium nitrate particles.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(7).
MLA	Dyson J.E.,et al."Production of HONO from NO2 uptake on illuminated TiO2 aerosol particles and following the illumination of mixed TiO2ĝ•ammonium nitrate particles".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.7(2021).