Intercalated cobalt porphyrin between layered double hydroxide nanosheets as an efficient and recyclable catalyst for aerobic epoxidation of alkenes

摘要

Anionic cobalt tetrasulfonatophenyl porphyrin (CoTPPS) intercalated Ni-Al LDH has been prepared through the exfoliation/restacking route. The obtained hybrids were characterized by XRD, SEM, TEM, IR, UV-Vis and TG-DSC. The volume ratio between the metalloporphyrin solution and LDH nanosheets suspension on the structure of restacking products was investigated and CoTPPS/Ni-Al LDH3.0 was found to exhibit the highest crystallinity. The interlayer spacing determined by XRD shows that CoTPPS was intercalated into the hyroxylated layers of LDH by a perpendicular orientation. The catalytic performance of the obtained hybrid material was investigated in the green epoxidation of various alkenes with oxygen as oxidant and isobutyaldehyde as co-reagent. The immobilized Co porphyrin demonstrated great application potential in oxidative catalysis, exhibiting exceptional stability and catalytic activity in oxidation of various alkenes.