气候变化领域集成服务门户(CCPortal): Photolytically induced changes in composition and volatility of biogenic secondary organic aerosol from nitrate radical oxidation during night-to-day transition

CCPortal

DOI	10.5194/acp-21-14907-2021
	Photolytically induced changes in composition and volatility of biogenic secondary organic aerosol from nitrate radical oxidation during night-to-day transition
	Wu C.; Bell D.M.; Graham E.L.; Haslett S.; Riipinen I.; Baltensperger U.; Bertrand A.; Giannoukos S.; Schoonbaert J.; El Haddad I.; Prevot A.S.H.; Huang W.; Mohr C.
发表日期	2021
ISSN	1680-7316
起始页码	14907
结束页码	14925
卷号	21 期号:19
英文摘要	Night-time reactions of biogenic volatile organic compounds (BVOCs) and nitrate radicals (NO3) can lead to the formation of NO3-initiated biogenic secondary organic aerosol (BSOANO3 ). Here, we study the impacts of light exposure on the chemical composition and volatility of BSOANO3 formed in the dark from three precursors (isoprene, α-pinene, and β-caryophyllene) in atmospheric simulation chamber experiments. Our study represents BSOANO3 formation conditions where reactions between peroxy radicals (RO2 + RO2) and between RO2 and NO3 are favoured. The emphasis here is on the identification of particle-phase organonitrates (ONs) formed in the dark and their changes during photolytic ageing on timescales of ∼1 h. The chemical composition of particle-phase compounds was measured with a chemical ionization mass spectrometer with a filter inlet for gases and aerosols (FIGAERO-CIMS) and an extractive electrospray ionization time-of-flight mass spectrometer (EESI-TOF). Volatility information on BSOANO3 was derived from FIGAERO-CIMS desorption profiles (thermograms) and a volatility tandem differential mobility analyser (VTDMA). During photolytic ageing, there was a relatively small change in mass due to evaporation (<5% for the isoprene and α-pinene BSOANO3, and 12% for the β-caryophyllene BSOANO3 ), but we observed significant changes in the chemical composition of the BSOANO3. Overall, 48%, 44%, and 60% of the respective total signal for the isoprene, α-pinene, and β-caryophyllene BSOANO3 was sensitive to photolytic ageing and exhibited decay. The photolabile compounds include both monomers and oligomers. Oligomers can decompose into their monomer units through photolysis of the bonds (e.g. likely O-O) between them. Fragmentation of both oligomers and monomers also happened at other positions, causing the formation of compounds with shorter carbon skeletons. The cleavage of the nitrate functional group from the carbon chain was likely not a main degradation pathway in our experiments. In addition, photolytic degradation of compounds changes their volatility and can lead to evaporation.We use different methods to assess bulk volatilities and discuss their changes during both dark ageing and photolysis in the context of the chemical changes that we observed. We also reveal large uncertainties in saturation vapour pressure estimated from parameterizations for the ON oligomers with multiple nitrate groups. Overall, our results suggest that photolysis causes photodegradation of a substantial fraction of BSOANO3, changes both the chemical composition and the bulk volatility of the particles, and might be a potentially important loss pathway of BSOANO3 during the night-to-day transition. © Author(s) 2021.
语种	英语
scopus关键词	aerosol composition; biogenic emission; light effect; nitrate; oxidation; photolysis; volatile organic compound
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/246526
作者单位	Department of Environmental Science, Stockholm University, Stockholm, Sweden; Laboratory of Atmospheric Chemistry, Paul Scherrer Institute, Villigen, Switzerland; Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, Helsinki, Finland; Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
推荐引用方式 GB/T 7714	Wu C.,Bell D.M.,Graham E.L.,et al. Photolytically induced changes in composition and volatility of biogenic secondary organic aerosol from nitrate radical oxidation during night-to-day transition[J],2021,21(19).
APA	Wu C..,Bell D.M..,Graham E.L..,Haslett S..,Riipinen I..,...&Mohr C..(2021).Photolytically induced changes in composition and volatility of biogenic secondary organic aerosol from nitrate radical oxidation during night-to-day transition.ATMOSPHERIC CHEMISTRY AND PHYSICS,21(19).
MLA	Wu C.,et al."Photolytically induced changes in composition and volatility of biogenic secondary organic aerosol from nitrate radical oxidation during night-to-day transition".ATMOSPHERIC CHEMISTRY AND PHYSICS 21.19(2021).