Three Birds with One Sulfur: Construction of Sulfur-Bridged Porous Organic Polymers for Efficient Gold Adsorption

Sulfur is a massive byproduct of the petrochemicals industry and hardly employed as a building block for porous organic polymers (POPs). Here, a new family of sulfur-bridged POPs has been prepared via a C-H insertion reaction between sulfur and polycyclic aromatic hydrocarbons. Sulfur works as a solvent, external cross-linker, and porogen simultaneously during the polymerization process. The products demonstrate high porosity and maximum surface area of 1050 m² g^-1 with abundant accessible active sites, contributing to the nanometerization of sulfur and significantly enhancing the inherent affinity between heteroatoms toward soft metal ions. Therefore, they exhibit a high absorption capacity for Au(III) of 3287 mg g^-1 and excellent absorption selectivity and removal efficiency via a performance evaluation even in real electronic wastewater. This synthetic strategy to prepare high added-value functional POPs with sulfur not only sheds light on designing high-performance gold adsorption materials and emerging POPs, but also promotes a sustainable development protocol.