Straightforward synthesis of beta zeolite encapsulated Pt nanoparticles for the transformation of 5-hydroxymethyl furfural into 2,5-furandicarboxylic acid

Encapsulating noble metal nanoparticles (NPs) within the zeolite framework enhances the stability and accessibility of active sites; however, direct synthesis remains a challenge because of the easy precipitation of noble metal species under strong alkali crystallization conditions. Herein, beta zeolite-encapsulated Pt NPs (Pt@Beta) were synthesized via a hydrothermal approach involving an unusual acid hydrolysis preaging step. The ligand-(3-mercaptopropyl)trimethoxysilane-and Pt precursor were cohydrolyzed and cocondensed with a silica source in an initially weak acidic environment to prevent colloidal precipitation by enhancing the interaction between the Pt and silica species. Thus, the resultant 0.2%Pt@Beta was highly active in the transformation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid (FDCA) under atmospheric O-2 conditions by using water as the solvent while stably evincing a high yield (90%) associated with a large turnover number of 176. The excellent catalysis behavior is attributable to the enhanced stability that inhibits Pt leaching and strengthens the intermediates that accelerate the rate-determining step for the oxidation of 5-formyl-2-furan carboxylic acid into FDCA. (C) 2021, Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

This study successfully synthesized beta zeolite-encapsulated Pt nanoparticles (Pt@Beta) using an unusual acid hydrolysis preaging step, demonstrating high catalytic activity and stability in the transformation reaction. The research provides a new approach for the application of noble metal nanoparticles in catalysis.