Defective molybdenum disulfide nanosheet for elemental mercury capture in simulated flue gas

Two-dimensional transition-metal dichalcogenides have gained increasing concerns because of their distinct structural features and also display great potential in mercury removal. Herein, a defect-rich MoS2 nanosheet is synthesized by using hydrothermal method and applied for adsorptive capture of elemental mercury (Hg-0) in simulated flue gas at low temperature. It exhibits excellent Hg-0 removal performance due to its ultra-thin lamellar and defective structures with ample exposed adsorption sites. The Hg-0 removal efficiency of the defective MoS2 nanosheet is all above 93% when the reaction temperature is within 25-150 degrees C. Besides, presence of NO has no influence on Hg-0 removal, while SO2 subtly reduces the Hg-0 removal efficiency due to competitive adsorption. Mo-4(+), S-2(-), and S-2(2-) ions take part in the Hg-0 removal process, which transfers Hg-0 into Mo-Hg amalgam and HgS. The process of Hg-0 adsorption on the defective MoS2 nanosheet obeys the pseudo-first-order and pseudo-second-order kinetic model. (C) 2020 Energy Institute. Published by Elsevier Ltd. All rights reserved.

Automated summary

A defect-rich MoS2 nanosheet was synthesized and applied for adsorptive capture of elemental mercury (Hg-0) in simulated flue gas at low temperature, showing excellent Hg-0 removal performance. The Hg-0 removal efficiency of the defective MoS2 nanosheet was all above 93% within the temperature range of 25-150 degrees C. Mo-4(+), S-2(-), and S-2(2-) ions participated in the Hg-0 removal process.