TY - JOUR
T1 - Oxidative dissolution of polymer-coated CdSe/ZnS quantum dots under UV irradiation
T2 - Mechanisms and kinetics
AU - Li, Yang
AU - Zhang, Wen
AU - Li, Kungang
AU - Yao, Ying
AU - Niu, Junfeng
AU - Chen, Yongsheng
N1 - Funding Information:
This study was partially supported by the U.S. Environmental Protection Agency Science to Achieve Results Program Grant RD-83385601 and Engineering Research Center (ERC)/Semiconductor Research Corporation (SRC)/ESH grant (425.025). The first and second authors contributed equally to this work.
PY - 2012/5
Y1 - 2012/5
N2 - To advance the knowledge of environmental fate of nanomaterials, we systematically investigated the dissolution of polymer-coated CdSe/ZnS quantum dots (QDs) under UV (254 nm) irradiation. The environmental effects (i.e., irradiation intensity, dissolved oxygen, temperature, and humic acid), as well as the coating effects on dissolution kinetics of QDs were investigated. Our results showed that higher irradiation intensity and temperature increased ion release rates (Cd 2+, SeO 4 2-, and Zn 2+), whereas the different polymer coatings varied the dissolution rates. The absence of dissolved oxygen inhibited the dissolution of QDs, and we further demonstrated that the dissolution was a photo-oxidative process involved superoxide radical formation. Humic acid had a twofold effect on dissolution due to its photosensitization and photoabsorption for UV irradiation. Finally, an empirical kinetic law was proposed to interpret the above environmental effects. This study lays groundwork to better understand the environmental fate of QDs.
AB - To advance the knowledge of environmental fate of nanomaterials, we systematically investigated the dissolution of polymer-coated CdSe/ZnS quantum dots (QDs) under UV (254 nm) irradiation. The environmental effects (i.e., irradiation intensity, dissolved oxygen, temperature, and humic acid), as well as the coating effects on dissolution kinetics of QDs were investigated. Our results showed that higher irradiation intensity and temperature increased ion release rates (Cd 2+, SeO 4 2-, and Zn 2+), whereas the different polymer coatings varied the dissolution rates. The absence of dissolved oxygen inhibited the dissolution of QDs, and we further demonstrated that the dissolution was a photo-oxidative process involved superoxide radical formation. Humic acid had a twofold effect on dissolution due to its photosensitization and photoabsorption for UV irradiation. Finally, an empirical kinetic law was proposed to interpret the above environmental effects. This study lays groundwork to better understand the environmental fate of QDs.
KW - Dissolution
KW - Kinetics
KW - QDs
KW - ROS
KW - UV Irradiation
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U2 - 10.1016/j.envpol.2012.01.047
DO - 10.1016/j.envpol.2012.01.047
M3 - Article
C2 - 22381580
AN - SCOPUS:84862818408
SN - 0269-7491
VL - 164
SP - 259
EP - 266
JO - Environmental Pollution
JF - Environmental Pollution
ER -