CeO<sub>2</sub> Nanoislands Enhance the Activity and Stability of Pt Nanoparticles Supported on Fibrous Mesoporous SiO<sub>2</sub> for Catalytic Combustion of Propane
Feng He, Cheng Rao, Songyun Tao, Liwei Sun, Ting Yi, Huaiyuan Wang, Bin Hu, Xiangguang Yang, Yibo Zhang
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.