Defect-driven unique stability of Pt/carbon nanotubes for propane dehydrogenation

Deactivation caused by the aggregation of Pt nanoparticles is a critical issue for the high-temperature propane dehydrogenation (PDH) reaction. Carbon nanotubes (CNTs) that were rich/poor in defects (CNTs-RD/CNTs-PD) were applied as supports for the PDH reaction. Pt nanoparticles supported on defect-rich CNTs (Pt/CNTs-RD) showed much higher performance and stability during the PDH reaction than those supported on defect-poor CNTs. X-ray photoelectron spectroscopy (XPS) results showed that there was little change between the fresh and spent Pt/CNTs-RD catalysts. High-resolution transmission electron microscopy (HRTEM) and simulation results both suggested the presence of strong metal-support interactions between the defects and Pt nanoparticles that could effectively inhibit the agglomeration of Pt nanoparticles, increase the anti-coking ability, and thus enhance the stability and activity of Pt/CNTs-RD during the high-temperature PDH reaction. The oxygen-containing groups and confinement effect of CNTs had a weaker influence on the catalyst activity.