Atomically dispersed Rh active sites on MOF-5 via defect engineering for hydroformylation of n-butene

Abstract

This work explored the role of defective sites on the hydroformylation of n-butene through ligand regulation. The investigation examined the effect of modulator properties on defect sites and rhodium loading, and optimized the H2BDC/modulator ratio to improve catalyst activity. Atomically dispersed Rh is anchored to these highly dispersed defect sites, effectively preventing aggregation and thereby enhancing hydrogenation ability. Under optimal conditions, the catalyst achieved a conversion of 96.9 %, with an overall aldehyde selectivity of 90 %. DRIFTS analysis provided compelling evidence that Rh(CO)2 and HRhCO species were formed on 1Rh/MOF-5-HBC, improving CO insertion capability. This study highlights the significance of MOFs as catalyst supports in enhancing performance through defect engineering. The ability of the modulator to induce defect formation was measured by pKa. Meanwhile, it has been discovered that the length differences between the modulator and the MOF organic ligand can have a significant impact on the stability of defective MOFs.