Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2024 Feb 29;1(4):247-258.
doi: 10.1021/acsestair.3c00041. eCollection 2024 Apr 12.

Chemical Composition and Optical Properties of Secondary Organic Aerosol from Photooxidation of Volatile Organic Compound Mixtures

Yumeng Cui  1 , Kunpeng Chen  1 , Haofei Zhang  2 , Ying-Hsuan Lin  1 , Roya Bahreini  1
Affiliations

Chemical Composition and Optical Properties of Secondary Organic Aerosol from Photooxidation of Volatile Organic Compound Mixtures

Yumeng Cui et al. ACS EST Air. .

Abstract

The chemical and optical properties of secondary organic aerosols (SOA) have been widely studied through environmental chamber experiments, and some of the results have been parametrized in atmospheric models to help understand their radiative effects and climate influence. While most chamber studies investigate the aerosol formed from a single volatile organic compound (VOC), the potential interactions between reactive intermediates derived from VOC mixtures are not well understood. In this study, we investigated the SOA formed from pure and mixtures of anthropogenic (phenol and 1-methylnaphthalene) and/or biogenic (longifolene) VOCs using continuous-flow, high-NOx photooxidation chamber experiments to better mimic ambient conditions. SOA optical properties, including single scattering albedo (SSA), mass absorption coefficient (MAC), and refractive index (RI) at 375 nm, and chemical composition, including the formation of oxygenated organic compounds, organic-nitrogen compounds (including organonitrates and nitro-organics), and the molecular structure of the major chromophores, were explored. Additionally, the imaginary refractive index values of SOA in the multi-VOC system were predicted using a linear-combination assumption and compared with the measured values. When two VOCs were oxidized simultaneously, we found evidence for changes in SOA chemical composition compared to SOA formed from single-VOC systems, and this change led to nonlinear effects on SOA optical properties. The nonlinear effects were found to vary between different systems.

PubMed Disclaimer

Conflict of interest statement

The authors declare no competing financial interest.

Figures

Figure 1
Figure 1
(a) SSA375 vs size parameter at 375 nm, (b) MAC375, and (c) k375 vs reaction time of SOA particles from five different systems. The open and closed markers represent the duplicate experiments.
Figure 2
Figure 2
Calculated (a) FC2H3O, (b) FCO2, (c) FON, and (d) FN-family of SOA particles from five different systems.
Figure 3
Figure 3
UPLC-DAD chromatograms (in negative mode) of (a) phenol, (b) 1-methylnaphthalene, (c) phenol + longifolene, and (d) 1-methylnaphthalene + longifolene samples. The x-axis is the UPLC retention time, and the y-axis is the DAD wavelength. Relative absorption intensity is color-coded, as shown in the legend.
Figure 4
Figure 4
Predicted k (k375,prd) vs measured k at 375 nm (k375,meas) for (a) phenol + longifolene and (b) 1-methylnaphthalene + longifolene SOA particles. The dashed lines are 1:1 lines.
See this image and copyright information in PMC

References

    1. Bond TC; Bergstrom RW. Light Absorption by Carbonaceous Particles: An Investigative Review. Aerosol Science and Technology. 2006, 40 (1), 27–67. 10.1080/02786820500421521. - DOI
    1. Andreae MO; Gelencsér A. Black carbon or brown carbon? The nature of light-absorbing carbonaceous aerosols. Atmos Chem. Phys. 2006, 6 (10), 3131–3148. 10.5194/acp-6-3131-2006. - DOI
    1. Laskin A.; Laskin J.; Nizkorodov SA. Chemistry of Atmospheric Brown Carbon. Chem. Rev. 2015, 115 (10), 4335–4382. 10.1021/cr5006167. - DOI - PubMed
    1. Intergovernmental Panel on Climate Change . Anthropogenic and Natural Radiative Forcing. In Climate Change 2013 - The Physical Science Basis; Cambridge University Press. 2013; pp 659–740. 10.1017/CBO9781107415324.018. - DOI
    1. Feng Y.; Ramanathan V.; Kotamarthi VR. Brown carbon: A significant atmospheric absorber of solar radiation. Atmos Chem. Phys. 2013, 13 (17), 8607–8621. 10.5194/acp-13-8607-2013. - DOI