Biomimetic mercury immobilization by selenium functionalized polyphenylene sulfide fabric

Highly efficient decontamination of elemental mercury (Hg⁰) remains an enormous challenge for public health and ecosystem protection. The artificial conversion of Hg⁰ into mercury chalcogenides could achieve Hg⁰ detoxification and close the global mercury cycle. Herein, taking inspiration from the bio-detoxification of mercury, in which selenium preferentially converts mercury from sulfoproteins to HgSe, we propose a biomimetic approach to enhance the conversion of Hg⁰ into mercury chalcogenides. In this proof-of-concept design, we use sulfur-rich polyphenylene sulfide (PPS) as the Hg⁰ transporter. The relatively stable, sulfur-linked aromatic rings result in weak adsorption of Hg⁰ on the PPS rather than the formation of metastable HgS. The weakly adsorbed mercury subsequently migrates to the adjacent selenium sites for permanent immobilization. The sulfur-selenium pair affords an unprecedented Hg⁰ adsorption capacity and uptake rate of 1621.9 mg g^-1 and 1005.6 μg g^-1 min^-1, respectively, which are the highest recorded values among various benchmark materials. This work presents an intriguing concept for preparing Hg⁰ adsorbents and could pave the way for the biomimetic remediation of diverse pollutants.