In-situ low-temperature sulfur CVD on metal sulfides with SO2 to realize self-sustained adsorption of mercury

Qinyuan Hong; Haomiao Xu; Xiaoming Sun; Jiaxing Li; Wenjun Huang; Zan Qu; Lizhi Zhang; Naiqiang Yan

doi:10.1038/s41467-024-47725-3

In-situ low-temperature sulfur CVD on metal sulfides with SO₂ to realize self-sustained adsorption of mercury

Nat Commun. 2024 Apr 18;15(1):3362. doi: 10.1038/s41467-024-47725-3.

Authors

Qinyuan Hong^#¹, Haomiao Xu^#², Xiaoming Sun¹, Jiaxing Li¹, Wenjun Huang¹, Zan Qu^{3

4}, Lizhi Zhang^{1

5}, Naiqiang Yan^{6

7}

Affiliations

¹ School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China.
² School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. xuhaomiao@sjtu.edu.cn.
³ School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. quzan@sjtu.edu.cn.
⁴ Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China. quzan@sjtu.edu.cn.
⁵ Key Laboratory of Pesticide & Chemical Biology of Ministry of Education Institute of Applied & Environmental Chemistry College of Chemistry, Central China Normal University, Wuhan, 430079, China.
⁶ School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 200240, China. nqyan@sjtu.edu.cn.
⁷ Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, China. nqyan@sjtu.edu.cn.

^# Contributed equally.

Abstract

Capturing gaseous mercury (Hg⁰) from sulfur dioxide (SO₂)-containing flue gases remains a common yet persistently challenge. Here we introduce a low-temperature sulfur chemical vapor deposition (S-CVD) technique that effectively converts SO₂, with intermittently introduced H₂S, into deposited sulfur (S_d⁰) on metal sulfides (MS), facilitating self-sustained adsorption of Hg⁰. ZnS, as a representative MS model, undergoes a decrease in the coordination number of Zn-S from 3.9 to 3.5 after S_d⁰ deposition, accompanied by the generation of unsaturated-coordinated polysulfide species (S_n^2-, named S_d^*) with significantly enhanced Hg⁰ adsorption performance. Surprisingly, the adsorption product, HgS (ZnS@HgS), can serve as a fresh interface for the activation of S_d⁰ to S_d^* through the S-CVD method, thereby achieving a self-sustained Hg⁰ adsorption capacity exceeding 300 mg g^-1 without saturation limitations. Theoretical calculations substantiate the self-sustained adsorption mechanism that S₈ ring on both ZnS and ZnS@HgS can be activated to chemical bond S₄ chain, exhibiting a stronger Hg⁰ adsorption energy than pristine ones. Importantly, this S-CVD strategy is applicable to the in-situ activation of synthetic or natural MS containing chalcophile metal elements for Hg⁰ removal and also holds potential applications for various purposes requiring MS adsorbents.

Grants and funding

21806105/National Natural Science Foundation of China (National Science Foundation of China)