Radical-constructed intergrown titanosilicalite interfaces for efficient direct propene epoxidation with H₂ and O₂

Area of Science:

• Materials Science
• Catalysis
• Nanotechnology

Background:

• Titanosilicates are key in oxidative catalysis due to their framework Ti sites.
• Existing titanosilicate catalysts (TS-1) have limitations in efficiency and activity.

Purpose of the Study:

• To develop novel titanosilicate catalysts with enhanced interfacial Ti sites.
• To improve propene oxide (PO) formation rate and catalyst efficiency.

Main Methods:

• Constructing intergrown MFI-type zeolite surfaces via UV-induced hydroxyl radicals.
• Synthesizing intergrown titanosilicalites and supporting gold (Au) species.
• Comparing catalytic performance with standard Au/TS-1 catalysts.

Main Results:

• Intergrown titanosilicalites showed a 2.1-fold increase in PO formation rate.
• Au efficiency improved by 3.0-fold compared to standard Au/TS-1.
• Mechanistic studies indicated lower-energy epoxidation pathways at interface Ti sites.

Conclusions:

• Zeolite intergrown interface sites offer a promising strategy for advanced catalysis.
• This approach can lead to improved epoxidation of various feedstocks.
• Further development of titanosilicate/silicalite-1/ZSM-5 interfaces is suggested.