The Catalyst of Ruthenium Nanoparticles Decorated Silicalite-1 Zeolite for Boosting Catalytic Soot Oxidation

Abstract

Herein, the Ruthenium nanoparticles (NPs) with the size of 12 nm were decorated on the hexagonal prism silicalite-1 (Ru/S-1) by the gas bubbling-assisted membrane reduction method (GBMR). The adsorption/activation properties are improved for reactant molecules due to the formation of an interfacial structure that enhances the interaction between the Ru NPs and S-1. The Ru/S-1 catalyst displays the highest catalytic activity (T50 = 356 °C) and CO2 selectivity (SCO2m = 99.9%). Moreover, no obvious deactivation was observed over the Ru/S-1 catalyst even after five cycles, and the values of T50 and SCO2m after cycling five times are similar to the fresh catalyst. The Ru/S-1 catalyst with excellent catalytic performance can be compared with a series of noble metal catalysts for soot oxidation. The catalytic mechanism of the Ru/S-1 catalyst was revealed by in situ characterization for soot oxidation. The interfacial effect between Ru NPs and S-1 plays an important role in the conversion of NO to NO2 during soot oxidation. Preparation of Ru/S-1 catalyst provides a hopeful way to obtain considerably low-cost and highly stable auto-exhaust treatment catalysts.