A Catalyst of Pd@MIL-101@SGO Catalyzes Epoxidation and Hydroxymethoxylation Tandem Reactions of Styrene

Bronsted acid and metal nanoparticles are important catalytic functional groups. In this work, a bifunctional heterogeneous catalyst with both strong Bronsted acid and metal nanoparticles was prepared. First Bronsted acid groups were obtained by sulfonating graphene oxide, next metal organic frameworks MIL-101 (Cr) grew on sulfonated graphene oxide (SGO), then palladium nanoparticles (NPs) were encapsulated in MIL-101@SGO composites. The catalyst was characterized by a variety of different techniques including XRD, SEM, TEM, EDS, FT-IR, TGA, and nitrogen physisorption measurements. Tandem heterogeneous catalysis of Pd@MIL-101@SGO was investigated for the one-pot direct conversion of styrene into beta-alkoxy alcohol. The catalyst retained high catalytic activity after 5 times of reuses in aqueous solutions. No loss of crystal structure was detected by PXRD and no leakage of Pd was detected by ICP-AES. Therefore, Pd@MIL-101@SGO proved to be an effective recyclable heterogeneous catalyst for synthesizing beta-alkoxy alcohol and exhibited potential application in industry.