TY - JOUR
T1 - Promoting effect of Rh-impregnation on Ag/CeO2 catalyst for soot oxidation
AU - Lee, Jae Hwan
AU - Kim, Min June
AU - Lee, Eun Jun
AU - Lee, Dae Won
AU - Kim, Chang Hwan
AU - Lee, Kwan Young
N1 - Funding Information:
This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) ( NRF-2016R1A5A1009592 ).
Publisher Copyright:
© 2021
PY - 2022/1/15
Y1 - 2022/1/15
N2 - In this study, the effect of Rh on the catalytic properties of CeO2 was examined using a series of Rh-impregnated catalysts with different Rh loadings (Rh(x)Ce, x = 1, 2, 3, 5 wt%). The Rh species were highly dispersed over CeO2, and Rh(x)Ce exhibited higher soot oxidation activity than CeO2. In particular, the H2-TPR and O2-TPD profiles of the prepared catalysts indicated that Rh(2)Ce outperformed all other Rh(x)Ce catalysts owing to its high reducibility and desorption of active oxygen species at low temperatures. Moreover, an excessive Rh loadings resulted in an increase in the Rh3+/Rh0 and a decrease in the surface oxygen reducibility of the Rh(x)Ce catalysts. Subsequently, the promoting effect of Rh on the catalytic properties of Ag/CeO2 was evaluated using a Rh-impregnated Ag/CeO2 catalyst (Rh(2)Ag(5)Ce). The Rh species were well-dispersed over Ag/CeO2, and Rh(2)Ag(5)Ce presented a higher catalytic activity than the Ag/CeO2 catalyst. XPS analysis revealed that the interaction between Rh and Ag caused changes in the electronic states of Rh and Ag. Moreover, the soot-TPR and Raman spectra data revealed that the Rh(2)Ag(5)Ce catalyst could use active oxygen species at a lower temperature and generate a higher amount of reactive oxygen species than all other analyzed catalysts. Furthermore, macroporous Rh(2)Ag(5)Ce exhibited excellent activity, which was ascribed to the high soot-catalyst contact efficiency.
AB - In this study, the effect of Rh on the catalytic properties of CeO2 was examined using a series of Rh-impregnated catalysts with different Rh loadings (Rh(x)Ce, x = 1, 2, 3, 5 wt%). The Rh species were highly dispersed over CeO2, and Rh(x)Ce exhibited higher soot oxidation activity than CeO2. In particular, the H2-TPR and O2-TPD profiles of the prepared catalysts indicated that Rh(2)Ce outperformed all other Rh(x)Ce catalysts owing to its high reducibility and desorption of active oxygen species at low temperatures. Moreover, an excessive Rh loadings resulted in an increase in the Rh3+/Rh0 and a decrease in the surface oxygen reducibility of the Rh(x)Ce catalysts. Subsequently, the promoting effect of Rh on the catalytic properties of Ag/CeO2 was evaluated using a Rh-impregnated Ag/CeO2 catalyst (Rh(2)Ag(5)Ce). The Rh species were well-dispersed over Ag/CeO2, and Rh(2)Ag(5)Ce presented a higher catalytic activity than the Ag/CeO2 catalyst. XPS analysis revealed that the interaction between Rh and Ag caused changes in the electronic states of Rh and Ag. Moreover, the soot-TPR and Raman spectra data revealed that the Rh(2)Ag(5)Ce catalyst could use active oxygen species at a lower temperature and generate a higher amount of reactive oxygen species than all other analyzed catalysts. Furthermore, macroporous Rh(2)Ag(5)Ce exhibited excellent activity, which was ascribed to the high soot-catalyst contact efficiency.
KW - Ag/CeO
KW - Reactive oxygen species
KW - Reducibility
KW - Rh
KW - Soot oxidation
UR - http://www.scopus.com/inward/record.url?scp=85116707135&partnerID=8YFLogxK
U2 - 10.1016/j.apsusc.2021.151504
DO - 10.1016/j.apsusc.2021.151504
M3 - Article
AN - SCOPUS:85116707135
SN - 0169-4332
VL - 572
JO - Applied Surface Science
JF - Applied Surface Science
M1 - 151504
ER -