A robust core-shell silver soot oxidation catalyst driven by Co3O4: Effect of tandem oxygen delivery and Co3O4-CeO2 synergy

Wang, Xin; Jin, Baofang; Feng, Rilu; Liu, Wei; Weng, Duan; Wu, Xiaodong; Liu, Shuang

doi:10.1016/j.apcatb.2019.03.019

Cited by 74 publications

(43 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…< near Figure 8 > Nevertheless, the attempts to establish correlations among the redox activities (reducibility behaviour) of both transition metal-catalysts and the soot combustion performance failed. Some studies reported that direct relationships among easiness of catalysts' reduction under reducing atmospheres (monitored by TPR-H2 or TPR-CO) and catalytic performance's under oxidative atmospheres are not fulfilled [36]. This is a clear example showing this lack of correlation.…”

Section: Fig 8 Depicts the Soot Conversions Profiles Versus Temperatmentioning

confidence: 97%

“…Co3O4 entities have been reported as a more active phase than CeO2 or Ag for NO oxidation under O2 presence [36]. Differently from CeO2-based materials, which are expected to follow a Mars-van-Krevelen route for soot oxidation under O2 presence, this possible route is completely overwhelmed when NOx is present for the case of Co3O4 entities, yielding a higher NO2-assisted soot combustion.…”

Section: < Near Figure 9 >mentioning

confidence: 99%

See 1 more Smart Citation

Catalytic activity of Cu and Co supported on ceria-yttria-zirconia oxides for the diesel soot combustion reaction in the presence of NOx

Yeste

Cauqui

Giménez-Mañogil

et al. 2020

Chemical Engineering Journal

View full text Add to dashboard Cite

In this work, copper and cobalt oxides supported on a ceria-yttria-stabilized zirconia (Ce-YSZ) have been studied as alternative to noble metals for the soot removal in diesel engines. The Ce-YSZ support was activated in order to obtain a catalyst with a high redox performance. The resulting catalysts were characterized by N2 physisorption, ICP, XRD, TPR-H2, TPR-CO, HAADF-STEM and XEDS.Additionally, their catalytic performance was evaluated in the NO oxidation to NO2 and in the combustion of soot in presence/absence of NOx. The Co/Ce-YSZ catalyst shows a maximum NO2 production activity higher than 70%, very close to that obtained with a commercial Pt catalyst used as a reference, and largely better than that of Cu/Ce-YSZ. A similar trend is observed in the combustion of soot in the presence of NOx, thus indicating the prevalence of the NO2-assisted mechanism for the oxidation of soot when NO2 is present. Results obtained with unsupported Co3O4and CuO oxides suggest that Co-containing catalyst is not only a better NO2 generator but also exhibits a more efficient utilization of NOx. Co3O4 entities would act as a pseudo-platinum phase allowing fresh supply of NO2 along the catalytic bed, thus accelerating the soot combustion reaction.However, if NOx is absent, the order of soot combustion rate matches with the performance in reducibility ("active oxygen" mechanism), the Cu catalyst being the most active in comparison with Co or Pt. Under these conditions, Ce-YSZ supported catalysts benefit from the excellent oxygenexchange properties of surface Ce-Y-Zr oxide nanostructures.

show abstract

Section: Fig 8 Depicts the Soot Conversions Profiles Versus Temperatmentioning

confidence: 97%

Section: < Near Figure 9 >mentioning

confidence: 99%

Catalytic activity of Cu and Co supported on ceria-yttria-zirconia oxides for the diesel soot combustion reaction in the presence of NOx

Yeste

Cauqui

Giménez-Mañogil

et al. 2020

Chemical Engineering Journal

View full text Add to dashboard Cite

show abstract

“…Cerium oxide is the most used catalyst for this aim due to its special oxygen storage capacity (OSC) that can create active oxygen species with excellent catalytic activity in the soot removal process . The modification with zirconia, , copper, , Co 3 O 4 , , or Cs 2 O has increased the performance reducing the temperature necessary for the particle elimination due to an increase in the oxygen mobility compared with CeO 2 since the addition of dopants to ceria promotes oxygen vacancies formation, redox properties, and oxygen storage capacity (OSC). On the other hand, the substitution by other materials without precious metals such as PrO x -3DOM, perovskites, or hydrotalcites has also been proposed as a suitable alternative for soot combustion in diesel engines in order to reduce the noble metal dependency.…”

Section: Introductionmentioning

confidence: 99%

Understanding of Soot Removal Mechanism over DeNOx-Catalysts as Passive Converters

Cortés‐Reyes

Herrera

Larrubia

et al. 2021

Ind. Eng. Chem. Res.

View full text Add to dashboard Cite

Although diesel particulate filters (DPFs) are able to efficiently remove soot and coupled NO x storage and reduction and selective catalytic reaction (NSR−SCR) technologies can considerably decrease NO x emissions, the elimination of soot over Pt−Ba− K/Al 2 O 3 and Cu-CHA NO x removal catalysts acting as passive converters is still an open topic. The estimation of the occurrence frequency and activation energy values from the distribution function of activation energy allowed the identification of sequential steps involved in the soot removal. For that, TG-MS nonisothermal experiments were carried out over the model of deNO x catalysts under a NO+O 2 atmosphere. For bare soot, only gas-phase components react with carbon particles to produce CO 2 at high temperatures with E a values higher than 120 kJ mol −1 for the direct oxidation by molecular oxygen and 114 kJ mol −1 for the assisted soot removal process by NO x . For the lean NO x trap (LNT) model catalyst, the combination of hydroxylated centers, provided by the incorporation of potassium responsible for the carbon elimination via gasification (70−90 kJ mol −1 ), and nitrate species stored onto the surface, involved in the elimination via oxidation (97 kJ mol −1 ), together with the gas-phase interaction, makes this catalyst an efficient soot passive converter. The Cu-SAPO-34 SCR catalyst with 4 wt % of copper located inside the framework and small pores of the chabazite structure are not able to act as a converter because soot removal takes place via assisted combustion with NO x and molecular oxygen, similar to the uncatalyzed process. CeO 2 , the main component of DPF, presented the lowest values of T 90 (923 K), ignition soot temperature, and activation energy due to the intervention of highly reactive oxygen species being the most effective soot converter in the low-temperature range.

show abstract

“…Table 4 shows the binding energies of Co 2p 1/2 and Co 2p 3/2 . It is known that the difference between these two levels is about 15.1 eV which indicates Co 3+ presence 39,40 . For all catalysts prepared by both methods in this work, the difference is higher than 15.1 eV which indicates that some Co 2+ (where the difference is about 16 eV) coexists with Co 3+ .…”

Section: Catalysts Characterizationmentioning

confidence: 99%

Catalytic feasibility of Ce-doped LaCoO3 systems for chlorobenzene oxidation: An analysis of synthesis method

Pérez

López

Cadús

et al. 2022

Journal of Rare Earths

View full text Add to dashboard Cite

A robust core-shell silver soot oxidation catalyst driven by Co3O4: Effect of tandem oxygen delivery and Co3O4-CeO2 synergy

Cited by 74 publications

References 52 publications

Catalytic activity of Cu and Co supported on ceria-yttria-zirconia oxides for the diesel soot combustion reaction in the presence of NOx

Catalytic activity of Cu and Co supported on ceria-yttria-zirconia oxides for the diesel soot combustion reaction in the presence of NOx

Understanding of Soot Removal Mechanism over DeNOx-Catalysts as Passive Converters

Catalytic feasibility of Ce-doped LaCoO3 systems for chlorobenzene oxidation: An analysis of synthesis method

Contact Info

Product

Resources

About