Synthesis of cyclodextrin-stabilized gold nanoparticles supported hierarchical zeolites for the facile production of furandicarboxylic acid (FDCA) from 5-hydroxymethylfurfural (HMF)

The development of gold nanoparticles (Au NPs)-based catalysts is a crucial issue in diverse catalytic applications due to their excellent activity. However, it often suffers from the Au NPs sintering at high temperatures, and therefore the aggregation of Au NPs to large particle sizes results in a decreased active surface area, eventually lowering a catalytic activity. To overcome these limitations, the rational design of small-scale and highly dispersed nanoparticles of gold on oxide supports is a challenging task in heterogeneous catalysis. In this contribution, we report an efficient concept to fabricate ultra-small gold nanoparticles supported on hierarchical ZSM-5 surfaces using cyclodextrin as a stabilizer with the particle size in the range of 1.3 ± 0.4 nm. In strong contrast to this, the large gold particles on zeolite surfaces are obtained approximately 3.6 ± 3.2 nm, when using a conventional impregnation method without a stabilizer. Consequently, the rationally designed ultra-small gold nanoparticles supported on hierarchical ZSM-5 can greatly promote high catalytic performance in HMF oxidation to FDCA with a yield of 75% under mild reaction condition. These findings emphasize the advantage of using cyclodextrin stabilized metallic nanoparticles supported on zeolite surfaces as heterogeneous catalysts for biomonomer production. This example opens up perspectives for the development of highly efficient catalytic materials of gold nanoparticle-zeolite interfaces for biorefinery applications. The AuCaZSM-5 zeolite with high dispersion of Au nanoparticles synthesized by deposition-precipitation method with γ-cyclodextrin and urea shows an effective conversion of 5-hydroxymethyl furfural (HMF) to 2,5-furandicarboxylic acid (FDCA). [Display omitted] •Au nanoparticles supported hierarchical ZSM-5 are fabricated using γ-cyclodextrin.•Integrating cyclodextrin and hierarchical structure allows improving Au dispersion.•The designer catalysts show great enhancement in selective HMF oxidation to FDCA.•Giving perspective of the design of NPs on non-reducible supports for biorefinery.