Sulfonate-grafted conjugated microporous polymers for fast removal of cationic dyes from water

Conjugated microporous polymers (CMPs) have gained great attention because of high surface area and permanent pores with good gas adsorption capability, but most of them are hard to disperse in water, and thus barely used in sewage disposal. Herein, we adopt sulfonation to post-synthesis sulfonate-grafted CMPs which possess unexceptional dispersity in water. The sulfonate-grafted CMPs also exhibit fast adsorption towards cationic dye solutions especially methylene blue (MB, maximum adsorption up to 1650 mg/g). Because of the porous structure, MB molecules interact with CMPs not only on the surface but also in pores, increasing the contact sites and adsorption efficiency. This research greatly expands the exploration and application scope of CMPs.