Matrix effects on the performance and mechanism of Hg removal from groundwater by MoS2 nanosheets

Wang，Mengxia1; Han，Qi1; Shu，Yufei1; Wang，Kunkun1; Wang，Li1; Liu，Bei1; Zucker，Ines1,2; Wang，Zhongying1

2022-04-01

10.1039/d1va00035g

Environmental Science: Advances   影响因子和分区

2754-7000

Mercury (Hg) contamination in groundwater has been recognized as a serious threat to human health and ecological systems all over the world. This study demonstrated that two-dimensional (2D) molybdenum disulfide (MoS) nanosheets can efficiently remove Hg in groundwater, with high Hg uptake capacity, ultrafast removal kinetics, and excellent selectivity. Interestingly, we found that the groundwater matrix has profound implications on the Hg removal efficiency and mechanisms by MoS nanosheets. Specifically, surface adsorption is the dominant removal mechanism for Hg in DI water owing to the high affinity between Hg(II) and MoS via strong Lewis acid/base soft–soft interactions. In groundwater, however, the presence of Cl renders HgClOH the dominant species, which can undergo adsorption onto MoS and homolytic cleavage to form thecHgCl radical. As an intermediate radical, cHgCl could either dimerize to form HgCl or further reduce to Hg. This reduction-based mechanism enhanced the overall removal capacity of Hg to 6288 mg g, which is among the highest values reported to date. Additionally, our desorption tests revealed the high stability of immobilized Hg on MoS nanosheets over conventional adsorbents in various extractant fluids. These impressive features render MoS nanosheets a promising candidate for remediation of Hg-contaminated groundwater.

英语

第一 ; 通讯

2-s2.0-85136124006

Scopus

1.State Environmental Protection Key Laboratory of Integrated Surface Water-Groundwater Pollution Control,Guangdong Provincial Key Laboratory of Soil and Groundwater Pollution Control,School of Environmental Science and Engineering,Southern University of Science and Technology,Shenzhen,518055,China
2.Porter School of Environmental Studies,School of Mechanical Engineering,Tel Aviv University,69978,Israel

Wang，Mengxia,Han，Qi,Shu，Yufei,et al. Matrix effects on the performance and mechanism of Hg removal from groundwater by MoS2 nanosheets[J]. Environmental Science: Advances,2022,1(1):59-69.

Wang，Mengxia.,Han，Qi.,Shu，Yufei.,Wang，Kunkun.,Wang，Li.,...&Wang，Zhongying.(2022).Matrix effects on the performance and mechanism of Hg removal from groundwater by MoS2 nanosheets.Environmental Science: Advances,1(1),59-69.

Wang，Mengxia,et al."Matrix effects on the performance and mechanism of Hg removal from groundwater by MoS2 nanosheets".Environmental Science: Advances 1.1(2022):59-69.