Dimensional Regulation of Titanosilicate by Kinetically Controlled Intergrowth Crystals

Abstract

AbstractDimensional regulation of titanosilicates from conventional 3D to revolutionary 2D without extra additives is limited by the Ostwald ripening process together with the mismatch of hydrolysis rate between Ti and Si species. Herein, the kinetically controlled and additive‐free strategy is devised to continuously regulate the dimensionality of intergrowth titanosilicate from 3D bulk to 2D nanosheets. The kinetic relative growth rate of orthorhombic MFI to tetragonal MEL (rMFI/rMEL) dominated by temperature control can determine the morphology of intermediates. Crisscross intermediates assembled by MFI branches along a direction and MEL connectors along a/b directions restrain the Ostwald ripening of titanosilicate and further transform into 2D nanosheets (≈2 nm), which show enhanced olefin epoxidation performance due to boosted diffusion ability. This kinetically controlled strategy unlocks green and efficient regulation of titanosilicate dimension.