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Generating hierarchical zeolites provides an effective way to enhance their transport and catalytic properties. Several seminal methods have been reported to fabricate them with mesoscopic periodic order using surfactant-like structure directing agents (SDAs). Nonetheless, designing SDAs to synthesize unidimensional hierarchical zeolites remains challenging, as their habitual growth along the channel direction is often unaffected by SDAs or growth modifiers. Herein, we report the synthesis of discus-architectured *MRE zeolite built up of crystalline domains registered in a decagonal, aperiodic order with designed polycationic ([–N+(CH3)2–C6H12–N+(CH3)2–C7H14–]n[Br−]2n) as a SDA. This hierarchical zeolite has abundant mesopores and exhibits a tenfold electron diffraction pattern similar to that of a quasicrystal due to the directional connection of nanodomains through 10-membered rings serving as rotational centers. The crystallization proceeds through oriented coalescence of polymorph domains with micropore channels normal to the discus. The material exhibits enhanced catalytic n-dodecane hydroisomerization performance, thanks to its strong acidity, reduced micropore channel length and presence of mesopores. The combination of crystalline order within each domain and aperiodic order for their arrangement diversifies structures for hierarchical zeolites and the design of polycationic SDAs expands the toolkit to generate them. [ABSTRACT FROM AUTHOR]

Despite offering remarkable advantages as solvents, double salt ionic liquids (DSILs) have been scarcely studied for extractive dearomatization from hydrocarbons as well as many other applications, thus urging a theoretical guidance method. In this work, a systematic framework combining the rational screening validation and mechanistic analysis is proposed for tailoring DSILs for the o‐xylene/n‐octane separation. From an initial pool of commercially available ionic liquids (ILs), key thermodynamic properties of paired DSILs are predicted by COSMO‐RS while their important physical properties are estimated from those of corresponding parent ILs (retrieved from experimental database or predicted by a deep learning model). Promising DSILs are tested by liquid–liquid equilibrium experiments, wherein the effect of ion ratio is also evaluated. The mechanism underlying the tunability of DSIL thermodynamic properties is disclosed by quantum chemistry calculation and molecular dynamics simulation. This work can be a valuable reference for guiding the design of DSILs for diverse applications. [ABSTRACT FROM AUTHOR]

Tailoring the morphology of zeolite crystals has the potential to improve their mass transport and catalytic properties, which critically relies on the design of organic structure directing agents (OSDAs). As a prototype for studying the nucleation and growth of zeolitic materials and a broadly used catalyst, MFI zeolite is often fabricated in the presence of molecular or surfactant types of OSDAs. Here, a polycation [–N+(CH2CH2CH3)2–(CH2)6–]n[OH−]n, which is conceptually equivalent to a bond-linked tetrapropyl ammonium cation (the normally used OSDA to generate MFI topology), is designed. The morphology of synthetic products depends on Na+ and Al contents in the initial sols. Highly crystalline, reduced a-axis (8–18 nm), and 36° rotationally intergrown nanosheets can be generated with Si/Al of 50 in the presence of Na+, while leaf-shaped bulky crystals growing along the b–c planes are obtained in the absence of Al or Na+. The control syntheses using polycations differ slightly in chain spacer, and branching lengths highlight the matching between the length of the methylene chain spacer and the length between micropore intersections for tailoring crystal anisotropic growth. The crystallization proceeds through three consecutive events: wrapping up of the polycation by inorganic precursors, nucleation and oriented alignment, requiring a prolonged induction period as the organization of inorganic precursor is sterically hindered. The hierarchical material exhibits high activity, stability and light olefin selectivity in n-heptane catalytic cracking owing to high crystallinity, improved diffusion property and strong acidity. The OSDA design concept opens a new avenue for manipulating zeolite structures to enhance their properties. [ABSTRACT FROM AUTHOR]