Stabilizing ultra-small bimetallic PtSn clusters within S-1 crystals for effective propane dehydrogenation with low Pt loading.

[Display omitted] • Ultra-small PtSn clusters were controlled through argon calcination atmosphere. • More than 8 g[C 3 H 6 ]·g[Pt]−1·h−1 of propylene formation rates were achieved. • Ultra-low deactivation constant of 0.0001 h−1 was evaluated for PtSn8@S-1-Ar-50. • The anticipating C 3 H 6 selectivity was owing to PtSn@S-1 confined-catalysis. It's a great challenge for enhancing the stability over Pt-based catalysts with low Pt loading during propane dehydrogenation based upon the manipulation of ultra-small PtSn clusters and their compositions. Here, we developed a novel strategy to produce and stabilize sub-nanometer PtSn clusters even atomical dispersion within Silicalite-1 crystals via tailoring calcination atmosphere from air to argon, which could achieve a stable performance of propane dehydrogenation with only 0.15 wt% Pt loading. Argon calcination atmosphere of PtSn@Silicalite-1 significantly decreased the size of PtSn clusters, which further presented a strikingly catalytic performance with the high formation of propylene over 8.0 mol[C 3 H 6 ]·g[Pt]−1·h−1 even after 3840 min at 600 °C (WHSV=760 g[C 3 H 8 ]·g[Pt]−1·h−1). Hardly any deactivation was obtained over PtSn8@S-1-Ar-50 after long-term runs for 3840 min with an extremely low deactivation constant of 0.0001 h−1 so far, which was mainly derived from the outstanding stability of PtSn sub-nanometers within S-1 crystals through appropriate flow rate of argon calcination atmosphere. [ABSTRACT FROM AUTHOR]