Self-assembly of three-dimensional zeolite imidazolate framework/anionic polyacrylamide network with enhanced hydrophilicity and water dispersibility for highly efficient water purification

Metal-organic frameworks (MOFs) have attracted widespread attention in recent years due to their high surface area and adjustable porosity. However, some MOFs such as ZIF-8 have strong hydrophobicity, which is not conducive to the purification of pollutants in water. Herein, we adopted a simple in-situ growth method to incorporate typical MOFs (ZIF-8, ZIF-67) to a low-cost hydrophilic anionic polyacrylamide (APAM) matrix to facilitate the dispersion of MOFs in water. The successful synthesis of ZIFs@APAM were verified by the comprehensive characterization of the synthesized material. The contact angle test proved the hydrophilicity of MOFs@APAM, indicating that MOFs@APAM composite materials were more prone to contact with pollutants in aqueous solutions. To test the potential of this material as a water treatment agent, the ability of ZIF-8 @APAMs to adsorb tetracycline from the water was evaluated, and the adsorption and removal reached 63.80% in 4 h, which had a 25.41% higher removal rate than pure ZIF-8. Also, ZIF-67 @APAM was evaluated to degrade rhodamine B by advanced oxidation in water, and the degradation reached 97.8% in 60 min and it can be looped multiple times.

Automated summary

The MOFs@APAM composite materials were successfully synthesized by in-situ growth method, showing improved water dispersibility and hydrophilicity for better contact with pollutants. ZIF-8 @APAM demonstrated superior adsorption and removal efficiency for tetracycline, while ZIF-67 @APAM achieved high degradation rate for rhodamine B in water.