Effect of rare earth (La, Nd, Pr, Sm and Y) on the performance of Pd/Ce0.67Zr0.33MO2−δ three-way catalysts

Recent advances in gasoline three-way catalyst formulation: A review

“…The same group also examined the same dopants for a Ce-rich Pd/Ce 0.67 Zr 0.33 O 2 catalyst (molar ratio of dopant to Ce: 1:8). 35 All dopants improved catalytic activity compared to the undoped Pd/CeZr, due to improved interactions between PdO and the catalyst support. Out of the five dopants, Pr and Nd showed the best low-temperature activity.…”

“…The T 50 of aged catalysts was as low as 267°C for HC oxidation, 267°C for NO reduction, and 186°C for NO 2 reduction ( Figure 6). 35 Zhou et al 36 also looked into the effect of Y, Nd, and Pr dopants, synthesizing a series of Pd/(0.4CeO 2 / 0.5ZrO 2 /0.05La 2 O 3 /0.05M) catalysts (M = Y 2 O 3 , Nd 2 O 3 , or Pr 2 O 3 ). Light-off temperatures achieved were slightly higher than those reported for the ceriarich Nd-or Pr-containing catalysts of Wang et al, despite a higher Pd loading (1 wt% vs 0.5 wt%).…”

Self-Regeneration Effect of Three-Way Catalysts during Thermal Aging Procedure

“…The deposition of carbon during the catalyst exploitation is a known phenomenon [39]. Thus, deposited carbon is often used as an internal standard for the XPS studies [40,41]. In our case, the assumed oxidation of carbon deposits is testified by the fact that in the regenerated sample, the carbon content is lower if compared with the StAR sample ( Table 2).…”

Enhanced properties of Pd/CeO2-nanorods modified with alkaline-earth metals for catalytic oxidation of low-concentration methane

“…In addition, γ , δ , ε and η peaks are attributed to the reduction of surface oxygen, surface Ce 4+ , subsurface oxygen and lattice oxygen from the bulk CeO 2 , respectively. 20–23 Among them, PdCa/CeO 2 -ND catalyst showed the lowest reduction temperature of γ and η peaks, indicating that addition of Ca made it have the highest redox capability, thus increased the oxygen mobility of the catalyst. Additionally, defects and oxygen vacancies can be introduced to the CeO 2 fluorite structure by doping of Ca, 11 and the introduction of Ca can also increase the active sites of the oxygen.…”

“…But diffraction peaks of Ca and Pd or PdO aren't still observed, suggesting that high temperature doesn't reunite the active species or less agglomeration below the detection limit of this XRD equipment. 20 The activities of PdCa/CeO 2 -ND ( n (Pd) : n (Ca) = 2 : 1) heated at different calcination temperature are shown in Fig. 9 .…”