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

J Am Chem Soc. 2023 Apr 26;145(16):9021-9028. doi: 10.1021/jacs.3c00309. Epub 2023 Apr 6.

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.