MoS2 quantum dots based MoS2/HKUST-1 composites for the highly efficient catalytic oxidation of elementary mercury

Due to the ever-tightening regulation on mercury emission in recent decades, there is an urgent need to develop novel materials for the removal of elemental mercury at coal-fired power plants. In this study, a series of MoS2 quantum dots (QDs)-based MoS2/HKUST-1 composite materials were prepared. It is found that MoS 2 QDs were encapsulated by HKUST-1 and enhanced the crystallinity and specific surface area of HKUST-1. The MoS2 /HKUST1 showed excellent performance in catalytic oxidation of Hg-0 as compared with pristine HKUST-1. It is found that surface layer of lattice oxygens is active and participates in Hg-0 oxidation, while the consumption of surface oxygens then leads to the formation of oxygen vacancies on the surface. These vacancies are effective in the adsorption and dissociation of O-2, which subsequently participates in the oxidation of Hg-0. Moreover, the study on the influence of commonly seen gas components, such as SO2, NO, NH3 and H2O, etc., on Hg-0 oxidation demonstrated that synergistic effects exist among these gas species. It is found that the presence of NO promotes the oxidation of Hg-0 using oxygen as the oxidant. (C) 2022 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.