Synthesis of multilamellar ZSM-5 nanosheets with tailored b-axis thickness

The ZSM-5 zeolite nanosheets are highly desired materials for catalytic reactions and membrane separation. Their synthesis depends on specially designed complex surfactants; however, the high-cost limits their large-scale industrial production. Herein, the tailored synthesis of coffin-shaped multilamellar ZSM-5 composed of orderly stacked 2D nanosheets is carried out using cetyltrimethylammonium bromide (CTAB) as a structure-directing agent (SDA) in the presence of silicalite-1 seed sol. The morphology and b -axis thickness of nanosheets is controlled by adjusting the amount of silicalite-1 seed sol, CTAB/TEOS ratio, SiO 2 /Al 2 O 3 ratio, and synthesis time. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) analysis indicate that the hydrophobic tail of CTAB acts as an inhibitor, effectively preventing the continuous growth along b -direction with an average thickness of 20–100 nm. This work highlights the role of silicalite-1 seed sol and CTAB in the orderly stacked sheets growth process. This crystallization strategy opens a facile and inexpensive approach for multilamellar ZSM-5 zeolite fabrication with 2D-nanosheets structures, and their practical applications in catalytic conversions of bulky molecules. • Multilamellar ZSM-5 crystals were successfully prepared by using CTAB as SDA in the presence of Silicalite-1 seed sol. • Multilamellar ZSM-5 nanosheets (30–100 nm) were synthesized with a short crystallization time of 12 h. • Stacking order of multilamellar ZSM-5 nanosheets (20–140 nm) along b-axis increased and then decreased with silicalite-1 seed sol and CTAB addition amount. • Aluminum content in synthetic gel has influence multilamellar ZSM-5 nanosheets noticeably.