Non-Stoichiometric BaMnCuO Perovskites as Catalysts for CO Oxidation: Optimizing the Ba Content.

In this work, a series of BaMnCuO samples (x: 1, 0.9, 0.8, and 0.

Optimizing the Catalytic Performance of BaCeMnO and BaLaCuMnO Perovskites for Soot Oxidation in Simulated GDI Exhaust Conditions.

BaCeMnO (BM-Ce) and BaLaMnCuO (BMC-La) perovskite-type mixed oxides were synthesized using the sol-gel method adapted for aqueous media with different values of x (0, 0.1, 0.3, 0.

Improving the Catalytic Performance of BaMnCuO Perovskite for CO Oxidation in Simulated Cars Exhaust Conditions by Partial Substitution of Ba.

The sol-gel method, adapted to aqueous media, was used for the synthesis of BaMnCuO (BMC) and BaAMnCuO (BMC-A, A = Ce, La or Mg) perovskite-type mixed oxides. These samples were fully characterized by ICP-OES, XRD, XPS, H-TPR, BET, and O-TPD and, subsequently, they were evaluated as catalysts for CO oxidation under different conditions simulating that found in cars exhaust. The characterization results show that after the partial replacement of Ba by A metal in BMC perovskite: (i) a fraction of the polytype structure was converted to the hexagonal BaMnO perovskite structure, (ii) A metal used as dopant was incorporated into the lattice of the perovskite, (iii) oxygen vacancies existed on the surface of samples, and iv) Mn(IV) and Mn(III) coexisted on the surface and in the bulk, with Mn(IV) being the main oxidation state on the surface.

Screening BaAMnO and BaAMnCuO (A = Mg, Ca, Sr, Ce, La) Sol-Gel Synthesised Perovskites as GPF Catalysts.

BaAMnO (BM-A) and BaAMnCuO (BMC-A) (A = Mg, Ca, Sr, Ce, La) perovskite-type mixed oxides were synthesised, characterised, and used for soot oxidation in simulated Gasoline Direct Injection (GDI) engine exhaust conditions. The samples have been obtained by the sol-gel method in an aqueous medium and deeply characterised. The characterization results indicate that the partial substitution of Ba by A metal in BaMnO (BM) and BaMnCuO (BMC) perovskites: (i) favours the hexagonal structure of perovskite; (ii) improves the reducibility and the oxygen desorption during Temperature-Programmed Desorption (O-TPD) tests and, consequently, the oxygen mobility; (iii) mantains the amount of oxygen vacancies and of Mn(IV) and Mn(III) oxidation states, being Mn(IV) the main one; and (iv) for BaAMnCuO (BMC-A) series, copper is partially incorporated into the structure.

Tailoring the Composition of BaBO (B = Fe, Mn) Mixed Oxides as CO or Soot Oxidation Catalysts in Simulated GDI Engine Exhaust Conditions.

Mixed oxides with perovskite-type structure (ABO) are promising catalysts for atmospheric pollution control due to their interesting and tunable physicochemical properties. In this work, two series of BaMnO and BaFeO (x = 1 and 0.7) catalysts were synthesized using the sol-gel method adapted to aqueous medium.