Zeolite-Confined PtSn Clusters

2160 h Sintering-Free

Passivating zeolite surface silanols keeps confined PtSn clusters sub-nanometer dispersed under high-temperature, hydrogen-free conditions.

Zhou, Jun · Su, Yang · Liu, Cun · Yang, Xiaofeng · Qiao, Botao

Angewandte Chemie - International Edition 2026

Specifications

On-stream time

{'zh': '2160', 'en': '2160'} h

Average PtSn cluster size

{'zh': '1.0', 'en': '1.0'} nm

Advantages

2160 h without sintering

After 2160 h on stream under hydrogen-free, pure propane at 550 °C, the PtSn alloy clusters retain an average size of only 1.0 ± 0.2 nm, showing that passivating surface silanols effectively suppresses sintering.

HF-free passivation

Uses hexamethyldisilazane (HMDS) as the silylating agent, avoiding the use of highly toxic hydrofluoric acid.

Clear mechanism

Passivation of external-surface and pore-mouth silanols eliminates hydroxyl anchoring and nucleation sites that would capture outward-migrating PtSn species and promote their nucleation and coalescence on the external zeolite surface.

Applications

• Propane Dehydrogenation：Directly used for propane dehydrogenation to propylene, replacing existing deactivation-prone catalysts.
• High-Temperature Catalysis：Suited for 550 °C high-temperature hydrogen-free conditions, solving high-temperature sintering.
• Zeolite Confinement：Enhances zeolite confinement to prevent metal species migration and coalescence.
• Sub-nanometer Alloys：Maintains sub-nanometer PtSn alloy size for high active site density.