Pt-based catalysts for direct propane dehydrogenation: Mechanisms revelation, advanced design, and challenges

Heterogeneous catalytic dehydrogenation of propane to produce propylene (PDH) has been considered an efficient technique in the olefins supply chains. Metallic Pt is recognized as a promising catalyst for PDH reaction on account of its excellent affinity to C-H bonds and C-H activation ability. However, monometallic Pt catalysts usually exhibit an unsatisfactory performance (poor selectivity toward propylene and low catalytic stability), which is attributed to the severe sintering of Pt particles and the coke formation during the dehydrogenation process. Various metal promoters (M) are ingeniously introduced into Pt-based catalysts functioning via the formation of Pt-M alloys and/or intermetallics. Besides, several supports suitable for Pt-based catalysts have been probed to achieve high Pt dispersion and strong metal-support interaction. In this review, we precede the introduction of promoters and supports applied in Pt-based catalysts with an overview of PDH reaction mechanism. The specific roles of the promoter addition along with the advantages and drawbacks of state-of-art supports are significantly highlighted. Current challenges and prospects for the future development of Ptbased catalysts are also discussed.