Dual-networks Enhanced Hollow ZIF-8 Particles for Water Treatment

Graphical Hollow ZIF-8 was embedded with polyphenol networks and polyethylene glycol networks. The double networks enhanced the stability of the hollow ZIF-8, showing promise in water treatment both by adsorption and photocatalysis. Hollow ZIF-8 particles are promising materials for water treatment because of the high porosity and catalytic activities under photon irradiation. However, hollow ZIF-8 particles can easily degrade under harsh conditions due to the weak stability. Here, we synthesize hollow ZIF-8 particles with polyphenol and polyethylene glycol networks embedded. The multiple interactions among the ZIF-8 frameworks and the networks increase the mechanical and chemical stability of the hollow ZIF-8 particles as suggested by a series of spectra. Uptake of methylene blue about 128 mg/g by the hollow particles is realized. Furthermore, hydroxyl or superoxide radicals for degradation of the adsorbed methylene blue are effectively generated through irradiation of the hollow ZIF-8 particles. In a water treatment test, the model pollute with a concentration of 50 mg/L is completely removed within half an hour. The performance of the recycled hollow ZIF-8 particles is proved to be significant, indicating the practical potential of the material.