Pd-promoted WO3-ZrO2 for low temperature NOx storage

Yaying Ji; Shuli Bai; Dongyan Xu; Dali Qian; Zili Wu; Yang Song; Robert Pace; Mark Crocker; Karen Wilson; Adam Lee; Deb Harris; Dave Scapens

doi:10.1016/j.apcatb.2019.118499

Pd-promoted WO₃-ZrO₂ for low temperature NOx storage

Yaying Ji, Shuli Bai, Dongyan Xu, Dali Qian, Zili Wu, Yang Song, Robert Pace, Mark Crocker, Karen Wilson, Adam Lee, Deb Harris, Dave Scapens

Research output: Contribution to journal › Article › peer-review

19 Scopus citations

Abstract

Pd-promoted ZrO₂ and WO₃-ZrO₂ (W-Zr) were investigated for low temperature NOx adsorption and release. Pd-promoted W-Zr exhibited high NOx storage efficiency at short storage times, subsequently releasing ∼95% of the stored NOx upon thermal ramping to 350 °C. DRIFTS studies demonstrated that Pd increased nitrate formation relative to nitrite during NOx storage on both Pd-Zr and Pd-W-Zr. Moreover, Pd sites on Pd-W-Zr played a major role in NOx storage, the ad-species being readily removed by 350 °C. From NO- and CO-DRIFTS data, it is inferred that Pd on the acidic W-Zr support was present as mainly cationic species, and was therefore able to adsorb NO, whereas on ZrO₂ Pd was not able to directly store NOx. Co-feeding CO with NO resulted in increased NOx storage capacity for Pd-W-Zr, which on the basis of DRIFTS measurements is attributed to the formation of Pd²⁺(CO)(NO) complexes.

Original language	English
Article number	118499
Journal	Applied Catalysis B: Environmental
Volume	264
DOIs	https://doi.org/10.1016/j.apcatb.2019.118499
State	Published - May 5 2020

Bibliographical note

Funding Information:
The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB 3 -Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences . The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Appendix A

Funding Information:
The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB3-Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences. The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility.

Publisher Copyright:
© 2019 Elsevier B.V.

Keywords

Cations
DRIFTS
Nitrosyl complex
Palladium
Passive NOx adsorber
Tungstated zirconia

ASJC Scopus subject areas

Catalysis
Environmental Science (all)
Process Chemistry and Technology

Access to Document

10.1016/j.apcatb.2019.118499

Cite this

@article{33fa3cb63c9147aa8b365aa7e7c18397,

title = "Pd-promoted WO3-ZrO2 for low temperature NOx storage",

abstract = "Pd-promoted ZrO2 and WO3-ZrO2 (W-Zr) were investigated for low temperature NOx adsorption and release. Pd-promoted W-Zr exhibited high NOx storage efficiency at short storage times, subsequently releasing ∼95% of the stored NOx upon thermal ramping to 350 °C. DRIFTS studies demonstrated that Pd increased nitrate formation relative to nitrite during NOx storage on both Pd-Zr and Pd-W-Zr. Moreover, Pd sites on Pd-W-Zr played a major role in NOx storage, the ad-species being readily removed by 350 °C. From NO- and CO-DRIFTS data, it is inferred that Pd on the acidic W-Zr support was present as mainly cationic species, and was therefore able to adsorb NO, whereas on ZrO2 Pd was not able to directly store NOx. Co-feeding CO with NO resulted in increased NOx storage capacity for Pd-W-Zr, which on the basis of DRIFTS measurements is attributed to the formation of Pd2+(CO)(NO) complexes.",

keywords = "Cations, DRIFTS, Nitrosyl complex, Palladium, Passive NOx adsorber, Tungstated zirconia",

author = "Yaying Ji and Shuli Bai and Dongyan Xu and Dali Qian and Zili Wu and Yang Song and Robert Pace and Mark Crocker and Karen Wilson and Adam Lee and Deb Harris and Dave Scapens",

note = "Funding Information: The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB 3 -Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences . The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Appendix A Funding Information: The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB3-Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences. The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Publisher Copyright: {\textcopyright} 2019 Elsevier B.V.",

year = "2020",

month = may,

day = "5",

doi = "10.1016/j.apcatb.2019.118499",

language = "English",

volume = "264",

}

TY - JOUR

T1 - Pd-promoted WO3-ZrO2 for low temperature NOx storage

AU - Ji, Yaying

AU - Bai, Shuli

AU - Xu, Dongyan

AU - Qian, Dali

AU - Wu, Zili

AU - Song, Yang

AU - Pace, Robert

AU - Crocker, Mark

AU - Wilson, Karen

AU - Lee, Adam

AU - Harris, Deb

AU - Scapens, Dave

N1 - Funding Information: The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB 3 -Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences . The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Appendix A Funding Information: The authors thank Shelley Hopps for XRD measurements. Drs. Christine Lambert and Joe Theis of Ford Motor Co. are thanked for helpful discussions. This project was funded by the National Science Foundation and the U.S. Department of Energy (DOE) under award no. CBET-1258742. However, any opinions, findings, conclusions, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the DOE. Funding from the British Council under the Global Innovation Initiative for the GB3-Net project is also gratefully acknowledged. Dr. Zili Wu was supported by the Center for Understanding and Control of Acid Gas-Induced Evolution of Materials for Energy (UNCAGE-ME), an Energy Frontier Research Center funded by U.S. Department of Energy, Office of Science, Basic Energy Sciences. The Raman work was conducted at the Center for Nanophase Materials Sciences, which is a DOE Office of Science User Facility. Publisher Copyright: © 2019 Elsevier B.V.

PY - 2020/5/5

Y1 - 2020/5/5

N2 - Pd-promoted ZrO2 and WO3-ZrO2 (W-Zr) were investigated for low temperature NOx adsorption and release. Pd-promoted W-Zr exhibited high NOx storage efficiency at short storage times, subsequently releasing ∼95% of the stored NOx upon thermal ramping to 350 °C. DRIFTS studies demonstrated that Pd increased nitrate formation relative to nitrite during NOx storage on both Pd-Zr and Pd-W-Zr. Moreover, Pd sites on Pd-W-Zr played a major role in NOx storage, the ad-species being readily removed by 350 °C. From NO- and CO-DRIFTS data, it is inferred that Pd on the acidic W-Zr support was present as mainly cationic species, and was therefore able to adsorb NO, whereas on ZrO2 Pd was not able to directly store NOx. Co-feeding CO with NO resulted in increased NOx storage capacity for Pd-W-Zr, which on the basis of DRIFTS measurements is attributed to the formation of Pd2+(CO)(NO) complexes.

AB - Pd-promoted ZrO2 and WO3-ZrO2 (W-Zr) were investigated for low temperature NOx adsorption and release. Pd-promoted W-Zr exhibited high NOx storage efficiency at short storage times, subsequently releasing ∼95% of the stored NOx upon thermal ramping to 350 °C. DRIFTS studies demonstrated that Pd increased nitrate formation relative to nitrite during NOx storage on both Pd-Zr and Pd-W-Zr. Moreover, Pd sites on Pd-W-Zr played a major role in NOx storage, the ad-species being readily removed by 350 °C. From NO- and CO-DRIFTS data, it is inferred that Pd on the acidic W-Zr support was present as mainly cationic species, and was therefore able to adsorb NO, whereas on ZrO2 Pd was not able to directly store NOx. Co-feeding CO with NO resulted in increased NOx storage capacity for Pd-W-Zr, which on the basis of DRIFTS measurements is attributed to the formation of Pd2+(CO)(NO) complexes.

KW - Cations

KW - DRIFTS

KW - Nitrosyl complex

KW - Palladium

KW - Passive NOx adsorber

KW - Tungstated zirconia

UR - http://www.scopus.com/inward/record.url?scp=85076276877&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85076276877&partnerID=8YFLogxK

U2 - 10.1016/j.apcatb.2019.118499

DO - 10.1016/j.apcatb.2019.118499

M3 - Article

AN - SCOPUS:85076276877

VL - 264

M1 - 118499

ER -