Rational design of interfacial sp C─S─Zn hybridization in ZnS/graphdiyne for mercury vapor capture

Capturing gaseous mercury (Hg⁰) from complex flue gases remains a common yet persistent issue. Here, the one-step hydrothermal method is adopted to synthesize zinc sulfide/graphdiyne (ZnS/GDY) nano adsorbents for efficient Hg vapor capture via a rational design of sp C─S─Zn hybridization on the interface. The research results indicate that GDY can gain electrons from ZnS though sp C─S─Zn bonds, which facilitates charge transfer and induces the generation of highly active Hg adsorption sites near sulfur defects (S_v). The fabricated ZnS/GDY adsorbent can achieve a Hg⁰ removal efficiency of 98% and exhibits excellent resistance to 1500 parts per million high-concentration sulfur dioxide (SO₂) constraints (maintaining a removal efficiency of 90.9%). Moreover, the commercial glass compound fiber filter (FMS) media coated with ZnS/GDY shows potential for application in bag filter systems. About 80% of Hg⁰ can be removed by ZnS/GDY@FMS, even under conditions of high SO₂ concentration and in the presence of dust. Our work demonstrates that efficient Hg⁰ removal efficiency under high-concentration SO₂ can be achieved by interfacial chemical bond engineering and provides guidance for functional carbon-based material design.