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Diesel exhaust emissions are major outdoor air pollutants. Reducing the emission of NOx by diesel commercial vehicles and related machineries is at present a great challenge. In this study, we synthesize a catalyst for low-temperature catalytic reduction of NO using calcinated UiO-66­(Zr) as a host for the doping of cerium, manganese, and titanium by the incipient wetness impregnation, followed by the dispersion of 1.0 wt % platinum. A solid solution of Ce0.15Zr0.54Mn0.11Ti0.20O2/1.0Pt (CZMTO/Pt) is synthesized as evident by the structural characterizations. The catalyst demonstrates significant NO reduction in the laboratory due to the synergistic effect of various elements, with NO conversion above 80% at 160 °C.

The demand for a dual catalyst that maintains high catalytic performance at low temperatures for simultaneous propane and carbon monoxide (CO) oxidation with repeated usage is significant, yet lacking in the literature. Here, we report a mesoporous platinum–ruthenium (0.5 wt % Pt and 0.5 wt % Ru)-doped ceria–zirconia bifunctional catalyst achieving T 95 at ∼260 °C and T 100 below 300 °C for propane oxidation, along with simultaneous 100% CO conversion at ∼200 °C. The performance is maintained after accelerated aging at 1000 °C for 24 h. The consistent superior performance over prolonged cycling is multifaceted, contributed by an optimal balance among nanostructure, metal oxide support/metal dopant system, and composition. The ceria–zirconia support gives enhanced oxygen storage and release capabilities coupled with thermal endurance. The porous catalyst has numerous catalytic sites with short reaction paths doped with Pt–Ru nanoparticles, leading to increased efficiency in bond cleavage for propane and endowing CO tolerance. Nanosized particles with narrow size distribution and uniform metal dispersion are effective in promoting catalytic activity toward oxidation reactions at low temperatures. This catalyst is thermally stable, durable, and active toward propane oxidation, and its catalytic performance is not compromised by the simultaneous presence of CO.