HPW/PDMAEMA-b-PMAA/ZIF-8 ternary lamellar composites and its photocatalytic degradation of methylene blue

摘要： PDMAEMA-b-PMAA block copolymers were prepared by sequential RAFT of DMAEMA and tBMA and followed by hydrolyzation. The phosphotungstic acid (HPW) was anchored to the PDMAEMA blocks via the electrostatic interaction. Then the obtained HPW-PDMAEMA-b-PMAA was added to the synthesis system of ZIF-8. During the formation of ZIF-8, the PMAA blocks with carboxyl groups can coordinate with Zn2+. The HPW anchored to the PDMAEMA blocks also interact with Zn2+. So the block copolymer can consolidate the interaction with HPW and ZIF-8 and prevent the leaking of HPW. At last, the HPW/PDMAEMA-b-PMAA/ZIF-8 ternary lamellar composites were obtained. The structure of HPW/PDMAEMA-b-PMAA/ZIF-8 hybrid material was characterized by powder X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). As a photocatalyst, the HPW/PDMAEMA-b-PMAA/ZIF-8 ternary lamellar composites showed the excellent photoactivity toward the degradation of methylene blue. The rate of degradation of MB is 0.0240 min-1, which is 7.5 times that of the commercially available P25 (0.0032 min-1). In the presence of H2O2, the kinetic degradation parameters of the composites achieved to 0.0634 min?1, which is about 19.8 times of P25.