Chemical synthesis and evaluation of Co₃O₄/Ce_0.9Zr_0.05Y_0.05O_2-δ mixed oxides for the catalytic-assisted combustion of soot

Soot is one of the primary atmospheric pollutants coming from incomplete combustion in diesel engines. Therefore, its mitigation is mandatory to preserve air quality and to diminish the already known harmful effects on human health. In the present work, it is studied the chemical synthesis of nanocrystalline powders of CeO₂-based oxides and their catalytic performance on the combustion of soot at low temperatures. Specifically, cerium oxide co-doped with zirconium and yttrium was successfully synthesized via hydrothermal synthesis and subsequently loaded with an active phase of Co₃O₄. The obtained catalysts were physicochemical, structural, and microstructurally characterized. Different samples were tested by thermogravimetric analysis looking forward to elucidating both the effect of the composition and other features of the catalyst on the soot combustion's kinetic and temperature. Results showed the obtaining of a high activity catalyst by reaching values of 255.4 and 327.2 °C for the T₁₀ and T₅₀, respectively. It is discussed the role of the Co₃O₄ acting as a promoter phase in the catalyst.