Regioselective Surface Assembly of Mesoporous Carbon on Zeolites Creating Anisotropic Wettability for Biphasic Interface Catalysis

Abstract

The anisotropic surface functionalization of microporous zeolites with mesoporous materials into hierarchically porous heterostructures with distinctive physical and chemical properties is expected to significantly extend their applicability to catalysis. However, the precise control of the surface chemistry of zeolite crystals through site-specific interconnection with mesoporous materials remains a grand challenge. Here, we report a regioselective surface assembly strategy for the region-specific growth of mesoporous polymer/carbon on zeolite nanocrystals. The approach enables controllable regioselective surface deposition of mesoporous polydopamine on the edges, curved surfaces, or/and flat surfaces of the silicalite-1 nanocrystals into exotic hierarchical nanostructures with diverse surface geometries. Upon carbonization, their derived heterostructures with anisotropic surface wettability show amphiphilic properties. As a proof of concept, Pt nanoparticle-encapsulated silicalite-1/mesoporous carbon nanocomposites are tested to be interface-active for forming Pickering emulsions. Significantly, the catalysts show superior catalytic performance in shape-selective hydrogenation of various nitroarenes in a series of biphasic tandem catalytic reactions, giving ∼100% yield of corresponding amine products. The results pave a path toward rational construction of high levels of surface structural complexity in hierarchically porous heterostructures for specific physical and chemical characteristics in diverse applications.

Construction of Three-Dimensional Dendritic Hierarchically Porous Metal–Organic Framework Nanoarchitectures via Noncentrosymmetric Pore–Induced Anisotropic Assembly

“…The TEM images confirm that the MOF nanoparticles with dendritic lamellar pore structure are formed only at a relatively high surfactant packing parameter when high values of P123/F127 mass ratios are employed in the reaction system (Figure S7). − Time-dependent TEM measurements were conducted to study the formation process of UiO-66 DHPNPs. Figures and S8 show the scheme model and structure of the intermediate products obtained at different time intervals in the reaction stages.…”

Anisotropic Interface Successive Assembly for Bowl-Shaped Metal–Organic Framework Nanoreactors with Precisely Controllable Meso-/Microporous Nanodomains

“…Amphiphilic-molecule-directed cooperative self-assembly is a universal solution-based approach to synthesize mesoporous nanoparticles. − Rational introduction of proper amphiphilic molecular soft templates and MOF precursors into a reaction system could allow for creating MOF nanostructures with mesoporous channels. − Nevertheless, achieving the anisotropic growth of mesoporous MOFs into nanoparticles with broken centrosymmetry, such as nanobowls, remains challenging due to the near-isotropic physiochemical environments present in the reaction systems. Furthermore, given the relatively lower stability of mesoporous MOFs with nanoscale pore walls compared to their microporous counterparts, , the design of a bowl-shaped core–shell structure, consisting of a partially exposed mesoporous MOF core protected by a microporous MOF shell, can not only enhance the structural stability of the mesoporous core but also increase accessibility to a substantial number of active sites located within the MOF core.…”

Enhancing Electrocatalytic Performance via Thickness-Tuned Hollow N-Doped Mesoporous Carbon with Embedded Co Nanoparticles for Oxygen Reduction Reaction

“…Geometrical construction is an effective method for influencing mass transfer in electrocatalysis, enabling the modulation of reactant activation, intermediate diffusion, and separation from reduced molecules. − This approach has garnered significant interest due to the advantages offered by high surface area and chemical/mechanical stability in mesoporous structures in recent years. − Furthermore, the mesoporous materials are frequently employed as a reaction medium to prepare metal nanoparticles. , Such a mesoporous structure restricts the production of nanoparticles and prevents them from aggregating . While the advantages of creating eave-like mesoporous hollow structures, such as a higher specific surface area, shorter charge and mass transport channels, and increased exposure of active sites, are evident, this aspect has not received extensive investigation.…”