CuO/CeO2 catalysts: Redox features and catalytic behaviors

Tang, Xiaolan; Zhang, Baocai; Li, Yong; Xu, Yide; Xin, Qin; Shen, Wenjie

doi:10.1016/j.apcata.2005.04.024

Cited by 209 publications

(119 citation statements)

References 39 publications

Supporting

Mentioning

103

Contrasting

Unclassified

Order By: Relevance

“…The copper or zinc-cooper deposition causes a decrease in the specific surface area around 10 and 20%, respectively. The S BET value of support is also lower than that reported by Tang et al 23 in spite of the use of a similar synthesis method. The discrepancies could be attributed to different calcination temperatures.…”

Section: Resultscontrasting

confidence: 45%

“…The authors have also attributed the first peak to disperse copper oxide clusters and the second arising from CuO particles strongly interacting with support but not incorporated into the support structure. Tang et al 23 have also reported two peaks at 140 and 173 °C for CuO(5 wt%)/CeO 2 whereas Wu et al 27 have observed three reduction peaks on CuO (10 wt.%)/CeO 2 catalysts with maxima at 148, 173 and 209 °C. The last authors have suggested that the first two peaks correspond to the reduction of CuO species while the third one was ascribed to the reduction of surface lattice oxygen in CeO 2 support.…”

Section: Resultsmentioning

confidence: 99%

“…In literature it was reported one or two TPR peaks for pure CeO 2 depending on the temperature range where the TPR experiment is carried out. 23,28 Tang et al 23 have reported one peak around 430 °C, whereas Markaryan et al 28 have informed two peaks. The first one at 500 ºC was assigned to the surface Ce +4 reduction, and the second one at about 850 ºC was attributed to reduction of bulk Ce +4 .…”

Section: -26mentioning

confidence: 99%

See 2 more Smart Citations

Methanol steam reforming over Cu/CeO2 catalysts: influence of zinc addition

Tonelli¹,

Gorriz²,

Arrúa³

et al. 2011

Quím. Nova

View full text Add to dashboard Cite

Recebido em 20/10/10; aceito em 17/3/11; publicado na web em 5/5/11Methanol steam reforming reaction was studied over Cu(5 wt.%)/CeO 2 with and without the presence of Zn. The Zn addition decreased the Cu +2 reducibility and increased the oxygen mobility of ceria. The main products were CO 2 and H 2 with small amount of CO. Selectivity to CO decreased with the Zn addition and it was lower at lower reaction temperatures and lower space velocities. At 230 ºC and W/F MeOH = 648 g min mol -1 selectivities to H 2 and to CO 2 were 100% on Zn/Cu/Ce. The catalytic results indicated that CO was mainly a secondary product formed from reverse water gas shift reaction.

show abstract

Section: Resultscontrasting

confidence: 45%

Section: Resultsmentioning

confidence: 99%

Section: -26mentioning

confidence: 99%

See 1 more Smart Citation

Methanol steam reforming over Cu/CeO2 catalysts: influence of zinc addition

Tonelli¹,

Gorriz²,

Arrúa³

et al. 2011

Quím. Nova

View full text Add to dashboard Cite

show abstract

“…The first one, centered about 932.8 eV, is attributed to reduced copper species and a second one, about 934.8 eV, can be ascribed Cu 2+ species. Moreover it is noticeable the presence of a shake-up satellite located about 942.1 eV [59]. The presence of reduced copper species can be elucidated by considering the intensity of the satellite contribution at high binding energy together with the intensity of the main peak (I sat /I mp ), this ratio being 0.55 if only CuO is present.…”

Section: Xpsmentioning

confidence: 99%

CuO-CeO2 supported on montmorillonite-derived porous clay heterostructures (PCH) for preferential CO oxidation in H2-rich stream

et al. 2015

View full text Add to dashboard Cite

a b s t r a c tThis study reports on the preparation and characterization of porous clay heterostructures (PCH) as a high-surface-area support for CuO-CeO 2 based catalysts for the preferential oxidation of CO in excess of H 2 (CO-PROX). After pillaring the montmorillonite clay with silica (Si-PCH) and silica-zirconia (SiZr-PCH), the Cu-Ce active phase was loaded by incipient wet impregnation setting the cerium amount constant (20 wt%) and investigating three different copper loadings (3, 6 and 12 wt%). The use of pillars of silica or silica-zirconia inserted in the interlayer space of a natural clay provides a high surface area support that can favor the dispersion of both CuO and CeO 2 active phases, leading to the formation of a high amount of copper-ceria interfacial sites, responsible for a very high catalytic activity in the CO-PROX reaction.The results obtained from characterization of the materials by XRD, N 2 physisorption, H 2 -TPR, XPS and CO 2 -TPD suggest that this synthesis method gives rise to catalysts with copper species highly active and selective for the CO-PROX reaction.The catalysts exhibit high CO conversion values and the sample with 6 wt% of copper on Si-PCH displays very good performances, comparable to those based on precious metal catalysts, even at low temperatures.The system reducibility was found modified by the incorporation of zirconium in the support, with a slight decrement of the CO conversion value, compared to the same material without Zr. The influence of the presence of CO 2 and H 2 O in the gas feed was also studied in order to simulate the real operating conditions of a PEMFC feed stream. Correlations between catalytic performances and physicochemical properties of the materials have been made.

show abstract

“…This peak is clearly due to the addition of copper that not only is reduced to Cu 0 , but can also promote CeO2 reduction through a spillover mechanism widely reported in literature for ceria supported metal catalysts [43,44]. At increasing CeO2 loading the peak tends to split into three features that are distinguished clearly on Cu10CZ80: the maxima have been related to the reduction of amorphous CuO clusters, bulk CuO interacting with surface ceria and CuO crystallites [45]. These three peaks are typical of ceria-supported CuO, so for this reason it is not surprising that they become evident only for high ceria loading.…”

Section: Resultsmentioning

confidence: 82%