Pt-Sn Alloy Nanoparticles Supported on Al₂O₃ for the Dehydrogenation of Octadecahydro-dibenzyltoluene

Abstract

The pair dibenzyltoluene/octadecahydro-dibenzyltoluene (H 0 -DBT/H 18 -DBT) as a promising liquid organic hydrogen carrier (LOHC) candidate could yield large-scale implementation in hydrogen storage and transport. Therefore, a LOHC-dehydrogenation catalyst with exceptional activity, product selectivity, and resistance against deactivation is of great importance. Herein, we synthesized a series of Pt-Sn/Al 2 O 3 alloy catalysts with different crystal structures of different Pt-Sn alloys and investigated the Pt-Sn allying process during the thermal decomposition of an organic bimetal salt [Sn(bpy) 3 ]PtCl 6 (bpy = 2–2′ bipyridine). Their activity and selectivity for the H 18 -DBT dehydrogenation reaction have been studied by tank and fixed-bed reactors. They obtain a 6–25 times TOF than the Pt-Sn catalyst prepared by the incipient wetness coimpregnation method. EXAS, HRTEM, CO-DRIFT, and other characterizations were used to characterize their structure, indicating that the bimetallic state Pt-Sn is the most active structure for the dehydrogenation of octadecahydro-dibenzyltoluene, and the Pt 3 Sn alloy is the most selective one. The impact of the alloying of Sn and Pt on the dehydrogenation performance of the catalyst was verified by using DFT calculations.