Antisintering Pd<sub>1</sub> Catalyst for Propane Direct Dehydrogenation with In Situ Active Sites Regeneration Ability
Mi Peng, Zhimin Jia, Zirui Gao, Ming Xu, Danyang Cheng, Meng Wang, Chengyu Li, Linlin Wang, Xiangbin Cai, Zheng Jiang, Hong Jiang, Ning Wang, Dequan Xiao, Hongyang Liu, Ding Ma
Abstract
Atomically dispersed Pd (Pd1) catalysts supported on annealed nanodiamond were prepared through a deposition–precipitation method toward propane direct dehydrogenation (PDDH). The Pd1 catalyst is superior to Pd cluster/particle catalysts in activity and stability. Combining experimental characterizations and DFT calculations revealed that atomically dispersed Pd species have strong interactions with the hybrid nanodiamond/graphene support, leading to better resistance to coke formation. More importantly, Pd sintering is inevitable in the cluster/particle catalysts, while the high dispersion of Pd species in Pd1 catalyst is well-preserved during the reaction, which is caused in part by the redistribution or migration of Pd single atoms onto the carbonaceous compound (coke). As a result, the Pd1 catalyst shows significantly better activity and stability in high-reaction temperatures than Pd cluster/particle catalysts. This work reveals deeper insights on designing highly dispersed metal catalysts with the ability of in situ regeneration of active sites in high-temperature catalytic reactions.