Synthesis Of Stable Metal-Organic Frameworks And Catalytic Performance Of Derived Composite Catalysts

Metal-organic frameworks(MOFs)have several of characteristics such as porosity,large specific surface area,adjustable functional structure and unsaturated metal sites.They have been widely explored in various fields.Some MOFs materials exhibt excellent thermal stability and chemical stability due to the strong coordination bond between high coordinate metal clusters and rigid organic ligands.MOFs also show excellent property when they are used for supported materials due to the unsaturated sites on the frameworks.Therefore,the researches on the synthesis of composite catalyst with MOFs as the supported material have attracted widely attention.For example,composite catalyst loaded with precious metal using MOFs as the support to improve the dispersity and reuseability of precious metal.In this paper,we select stable UiO-66 and MIL-88 A as the main study object and investage the effect of modulator and solvation on the morphology of MOFs.Then Ferrocene@UiO-66 and Ag/AgCl@MIL-88 A were synthesized by loading the ferrocene,Ag and AgCl nanoparticles,respectively.In addition,the catalytic or photocatalytic activities of as-synthesized composite were evaluated by phenol hydroxylation and degradation of rhodamine B,respectively.This study found that the effect of modulator and strong solvation could slow down the process of crystal growth and then improve the morphology and dispersity of as-synthesized MOFs.Ferrocene@UiO-66 exhibited good catalytic activity in the hydroxylation of phenol,in which the conversion of pehol is 38.5% and the yield of dihydroxybenzene is 87.4% under optimized reaction condition.Comparing with conventional support,Ferrocene@UiO-66 composites with UiO-66 as support could shorten the reaction time greatly and show better catalytic activity in the phenol hydroxylation.Meanwhile Ag/AgCl@MIL-88 A also showed good photocatalytic activity in the photocatalytic degradation of rhodamine B.Thereinto,Ag/AgCl@s-MIL-88 A had the best photocatalytic activity.Under the condition of simulated sunlight,the degradation rate of rhodamine B solution(100mL,20mg/L)was 97.7% after lighting 10 min.Under the condition of visible light,the degradation rate of rhodamine B solution(100mL,20mg/L)was 98.8% after lighting 100 min.