BaTi0.8Cu0.2O3 Catalysts for NO Oxidation and NOx Storage: Effect of Synthesis Method

Abstract

The effect of the synthesis method (sol-gel or hydrothermal) in the physicochemical properties of a BaTi 0.8 Cu 0.2 O 3 catalyst with perovskite structure was analyzed and the catalytic performance for the NO-NO 2 oxidation and for the NO x storage was tested. The characterization of catalysts by BET, ICP-OES, XRD, XPS and H 2 -TPR reveals that only the sol-gel process allows the incorporation of copper into the perovskite structure, and that, by using the hydrothermal method, highly dispersed CuO is deposited on the surface of the BaTiO 3 . The NO x storage cyclic (NSC) experiments, carried out using both catalysts, indicate that sol-gel catalyst shows a high NO x storage capacity at 400°C whilst the hydrothermal catalyst exhibits a high NO to NO 2 oxidation activity. For this reason, a double bed reactor configuration was tested for NSC experiments using the hydrothermal catalyst as the oxidation catalyst and the sol-gel catalyst as the NO x trap.

BaFe1−xCuxO3 Perovskites as Soot Oxidation Catalysts for Gasoline Particulate Filters (GPF): A Preliminary Study

“…These results agree with that reported for coppersupported Ceria-zirconia catalysts for soot oxidation in GDI conditions [9]." "Copper content has a key role on the performance of the BaFe1-xCuxO3 catalyst for soot oxidation, which is in agreement with previous reports focused on diesel soot removal [13][14][15][16][17][27][28][29][30] and with that reported for copper-supported Ceria-zirconia catalysts for soot oxidation in GDSI conditions [9]." Answer to Reviewer #2 The authors synthesized composite oxides of Cu, Fe and Ba by a citrate sol-gel method, and investigated the properties and activities of the compounds obtained by their composition ratio.…”

“…The results of the Rietveld analysis confirm the structural modification detected by XRD. A sentence indicating this fact has been added to the manuscript: "This structural modification (which has been confirmed by the Rietveld analysis shown in Figure S1 in Supplementary information), was previously observed for other bariumbased perovskites [13,14,17] and also for Sn-doped BaFeO3 perovskites [18], seems to evidence the copper introduction into the perovskite lattice..", 3-Does the Cu segregation up to a certain load of Cu influence the catalytic activity? As it is discussed in the Catalytic activity section, the presence of copper species as segregated phase (BaOx-CuOx) seems to justify that BFC4 presents the highest activity as copper oxides are a well-known catalysts for oxidation reaction.…”

“…The XRD patterns of the BFC0 and BFC1 catalysts, shown in Figure 1, reveal hexagonal perovskite structure as the main crystalline phase, even though these two catalysts also show a Fe(III) and Fe(IV) mixed-oxide with triclinic structure as a minority phase. Moreover, the decrease in the intensity of the main perovskite peak (at ca.31.5º) of BFC1 catalyst indicates that copper has been satisfactorily incorporated into the perovskite structure [13][14]17]. In contrast, XRD patterns of BFC3 and BFC4 catalyst fit with a cubic perovskite structure.…”

Perovskite-Based Catalysts as Efficient, Durable, and Economical NOx Storage and Reduction Systems

“…In these materials, the presence of BaCO3 as an impurity promoted the NOx adsorption capacity; however, this phase limited the regeneration capacity after SO2 poisoning. More recently, perovskites BaFe0.8Ti0.2O3 [85] and BaFe0.8Cu0.2O3 [75,86] have been proposed as alternative formulations. Alternatively, La-based perovskites have been extensively studied in recent years due to their excellent NO oxidation conversion and structural stability.…”

An Eco-Friendly Method of BaTiO3 Nanoparticle Synthesis Using Coconut Water

“…BaTiO 3 also exhibits piezoelectric, pyroelectric, and catalytic properties, suitable for sonar and infrared detectors [4], oxidation catalysts [5], and photocatalysts [6].…”