Subcrystal-Mediated Hetero-Crystallization Enables Phase-Controlled Zeolite Intergrowths with Multidimensional Disorder

Phase-controlled synthesis and comprehensive structural understanding of intergrowth zeolites remain challenging because of kinetic competition during crystallization and oversimplified structural models. Differences in nucleation kinetics between competing frameworks and framework interconversion during crystallization can decouple the initial synthesis composition from the final phase composition, while conventional stacking models cannot fully describe their structural complexity. Here, we develop a subcrystal-mediated heterocrystallization strategy using highly active ZSM-5 (MFI) and ZSM-11 (MEL) subcrystals (<10 nm) as preorganized building units. Mixing the isolated ZSM-5 and ZSM-11 subcrystals at defined ratios under mild conditions bypasses the kinetic bias associated with the faster ZSM-5 nucleation and suppresses framework interconversion, enabling ratio-directed control over MFI/MEL phase composition. Time-resolved crystallization and persistently low concentrations of soluble species support a predominantly particle-attachment-dominated nonclassical pathway rather than extensive dissolution-regrowth. Atomic-resolution imaging combined with T12-unit analysis resolves multidimensional disorder beyond conventional one-dimensional intergrowth models, revealing two-dimensional structural disorder, diverse channel architectures, corresponding connector motifs, and connected or interrupted interfaces that accommodate 90°-rotated intergrowth. Variations in phase composition are accompanied by systematic changes in pore characteristics and acidity, together with tunable molecular diffusion and catalytic behavior. This combined control of crystallization kinetics and multidimensional structural complexity provides a general platform for engineering intergrown zeolites with tailored functionalities.