From nano aggregates to nano plates: The roles of gelatin in the crystallization of titanium silicate-1

A simple strategy for tuning the morphology of titanium silicalite-1 (TS-1) from nano aggregates to b-axis-oriented plate was provided. The b-axis length of TS-1 can be adjusted from ~40 nm to ~300 nm by varying the amount of a sustainable and cheap commercial regulator gelatin. The functional mechanism of gelatin was studied systematically. It not only plays a significant role in the formation of plate-like morphology, but also affects the coordination states of Ti cations. Octahedrally coordinated Ti and anatase TiO2 was eliminated at proper gelatin adding amounts. The synergetic effect of amino and carboxyl groups is the primary aspect for influencing morphology. The TS-1 catalysts were evaluated in the epoxidation of cyclohexene. Both the nano aggregates and plates show better catalytic performances than the bulk TS-1, due to the reduced extraframework Ti and improved diffusion property.