CeO₂ Nanoislands Enhance the Activity and Stability of Pt Nanoparticles Supported on Fibrous Mesoporous SiO₂ for Catalytic Combustion of Propane

Abstract

The size of precious metal catalysts plays an important role in their activity, and inhibiting precious metal aggregation or even sintering is a major challenge in practical industrial applications. Herein, the physical limitation of fibrous mesoporous silica (KCC-1) and Pt–CeO 2 interaction of CeO 2 nanoislands were designed and used to inhibit the size of Pt particles, thereby improving their intrinsic activity and thermal stability. With the introduction of CeO 2 nanoislands, the turnover frequency (TOF) value of the Pt–CeO 2 /KCC-1 catalyst for propane-catalyzed combustion at 210 °C was 1.5 times that of Pt/KCC-1 and 5.6 times that of Pt/CeO 2 . Moreover, after aging at 800 °C, Pt–CeO 2 /KCC-1 showed enhanced thermal stability compared with Pt/KCC-1 due to the smaller change in the Pt size. Through comprehensive characterization and research of the reaction mechanism, the results indicate that due to the Pt–CeO 2 interaction, the Pt species were confined to the middle of the CeO 2 nanoisland, which was further separated by fiber sheets of KCC-1, to advance the activity and thermal stability of the catalyst. The strategy of the nanoisland in this paper provides guidance for designing better catalysts for other harsh reaction conditions.