TY - JOUR
T1 - Water-Insoluble Organics Dominate Brown Carbon in Wintertime Urban Aerosol of China
T2 - Chemical Characteristics and Optical Properties
AU - Huang, Ru Jin
AU - Yang, Lu
AU - Shen, Jincan
AU - Yuan, Wei
AU - Gong, Yuquan
AU - Guo, Jie
AU - Cao, Wenjuan
AU - Duan, Jing
AU - Ni, Haiyan
AU - Zhu, Chongshu
AU - Dai, Wenting
AU - Li, Yongjie
AU - Chen, Yang
AU - Chen, Qi
AU - Wu, Yunfei
AU - Zhang, Renjian
AU - Dusek, Ulrike
AU - O'Dowd, Colin
AU - Hoffmann, Thorsten
N1 - Funding Information:
This work was supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 41877408, 41925015, 91644219, and 41675120, the Chinese Academy of Sciences (No. ZDBS-LY-DQC001), the National Key Research and Development Program of China (No. 2017YFC0212701), and the Cross Innovative Team fund from the State Key Laboratory of Loess and Quaternary Geology (No. SKLLQGTD1801).
Funding Information:
This work was supported by the National Natural Science Foundation of China (NSFC) under Grant Nos. 41877408, 41925015 91644219, and 41675120, the Chinese Academy of Sciences (No. ZDBS-LY-DQC001) the National Key Research and Development Program of China (No. 2017YFC0212701) and the Cross Innovative Team fund from the State Key Laboratory of Loess and Quaternary Geology (No. SKLLQGTD1801).
Publisher Copyright:
Copyright © 2020 American Chemical Society.
PY - 2020/7/7
Y1 - 2020/7/7
N2 - The chromophores responsible for light absorption in atmospheric brown carbon (BrC) are not well characterized, which hinders our understanding of BrC chemistry, the links with optical properties, and accurate model representations of BrC to global climate and atmospheric oxidative capacity. In this study, the light absorption properties and chromophore composition of three BrC fractions of different polarities were characterized for urban aerosol collected in Xi'an and Beijing in winter 2013-2014. These three BrC fractions show large differences in light absorption and chromophore composition, but the chromophores responsible for light absorption are similar in Xi'an and Beijing. Water-insoluble BrC (WI-BrC) fraction dominates the total BrC absorption at 365 nm in both Xi'an (51 ± 5%) and Beijing (62 ± 13%), followed by a humic-like fraction (HULIS-BrC) and high-polarity water-soluble BrC. The major chromophores identified in HULIS-BrC are nitrophenols and carbonyl oxygenated polycyclic aromatic hydrocarbons (OPAHs) with 2-3 aromatic rings (in total 18 species), accounting for 10% and 14% of the light absorption of HULIS-BrC at 365 nm in Xi'an and Beijing, respectively. In comparison, the major chromophores identified in WI-BrC are PAHs and OPAHs with 4-6 aromatic rings (in total 16 species), contributing 6% and 8% of the light absorption of WI-BrC at 365 nm in Xi'an and Beijing, respectively.
AB - The chromophores responsible for light absorption in atmospheric brown carbon (BrC) are not well characterized, which hinders our understanding of BrC chemistry, the links with optical properties, and accurate model representations of BrC to global climate and atmospheric oxidative capacity. In this study, the light absorption properties and chromophore composition of three BrC fractions of different polarities were characterized for urban aerosol collected in Xi'an and Beijing in winter 2013-2014. These three BrC fractions show large differences in light absorption and chromophore composition, but the chromophores responsible for light absorption are similar in Xi'an and Beijing. Water-insoluble BrC (WI-BrC) fraction dominates the total BrC absorption at 365 nm in both Xi'an (51 ± 5%) and Beijing (62 ± 13%), followed by a humic-like fraction (HULIS-BrC) and high-polarity water-soluble BrC. The major chromophores identified in HULIS-BrC are nitrophenols and carbonyl oxygenated polycyclic aromatic hydrocarbons (OPAHs) with 2-3 aromatic rings (in total 18 species), accounting for 10% and 14% of the light absorption of HULIS-BrC at 365 nm in Xi'an and Beijing, respectively. In comparison, the major chromophores identified in WI-BrC are PAHs and OPAHs with 4-6 aromatic rings (in total 16 species), contributing 6% and 8% of the light absorption of WI-BrC at 365 nm in Xi'an and Beijing, respectively.
UR - http://www.scopus.com/inward/record.url?scp=85088209875&partnerID=8YFLogxK
U2 - 10.1021/acs.est.0c01149
DO - 10.1021/acs.est.0c01149
M3 - Article
C2 - 32479722
AN - SCOPUS:85088209875
SN - 0013-936X
VL - 54
SP - 7836
EP - 7847
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 13
ER -