In Situ-Formed PtMn Intermetallic Subnanoclusters on Mn-Doped Mesoporous Al₂O₃ as Efficient Catalysts for Propane Dehydrogenation

Abstract

Pt-based catalysts have been widely investigated for propane dehydrogenation (PDH) due to their superior activation of C−H bonds. It is still a challenge to develop highly dispersed Ptbased catalysts with an excellent PDH performance. Herein, we designed in situ-formed PtMn intermetallic nanoclusters on Mndoped mesoporous Al 2 O 3 as efficient catalysts for PDH. A series of characterizations demonstrated that well-dispersed PtMn intermetallic nanoclusters were in situ-formed and did not aggregate into large ensembles during PDH reactions. The PtMn intermetallic nanoclusters reduced the activation temperature of C−H cleavage and improved the PDH performance. The specific activity of the Pt/2Mn-Al 2 O 3 catalyst was 0.81 mol C3H6 mol Pt −1 s −1 at 600 °C, which is comparable to that of most of the state-of-theart PtM bimetallic nanocatalysts. Moreover, the catalyst exhibited better stability than the undoped catalyst, which resulted from the antisintering effect of the PtMn intermetallic nanoclusters and the migration of coke from the Pt sites to the support. Thus, the Pt/ 2Mn-Al 2 O 3 catalyst exhibited excellent regeneration stability with recoverable propane conversion and selectivity for propylene after removing coke.