TiO2 Supported RuRe Nanocatalysts for Soot Oxidation: Effect of Re and the Support Nature

Catalytic combustion of hazardous particulate matter (soot) generated by automobile engines is a primary method of their elimination. Ruthenium-based catalysts are a promising alternative for traditional noble metal (Pt, Pd) based systems; however, their relatively poor thermal stability hinders wide applications. In this study, we synthesized a novel, highly active, and stable catalyst for soot oxidation containing bimetallic RuRe nanoparticles supported on TiO 2 . The RuRe NPs were synthesized by colloidal, microwave-assisted polyol method and deposited on rutile or anatase TiO 2 . The effect of rhenium content and the nature of TiO 2 support on the performance of RuRe nanoparticles (NPs) in the soot oxidation under air atmosphere was investigated. Bimetallic RuRe/TiO 2 nanocatalysts exhibited higher activity in the soot oxidation than Ru/TiO 2 systems, and the rutile supported 2 wt% Ru–0.4 wt% Re nanocatalyst (Ru/Re atomic ratio of 9:1) showed the best catalytic performance (T 50 = 340 °C and T 90