TY - JOUR
T1 - A combined DRIFTS and MS study on reaction mechanism of NO reduction by CO over NiO/CeO2 catalyst
AU - Cheng, Xiaoqing
AU - Zhu, Aimin
AU - Zhang, Yuzhuo
AU - Wang, Yong
AU - AU, Chak Tong
AU - Shi, Chuan
N1 - Funding Information:
The work was supported by the National Natural Science Foundation of China (Nos. 20573014 and 20077005) and by the Program for New Century Excellent Talents in University (NCET-07-0136), as well as by the National High Technology and Development Program (863 program) of China (Grant No. 2007AA06Z311).
PY - 2009/8/17
Y1 - 2009/8/17
N2 - Previously, we reported the prominent catalytic activity of ceria-supported nickel oxide catalyst for the reduction of NO by CO [Y. Wang, A.M. Zhu, Y.Z. Zhang, C.T. Au, X.F. Yang, C. Shi, Appl. Catal. B 81 (2008) 141-149]. In the present study, the reaction mechanism of NO and CO over the NiO/CeO2 catalyst has been examined in two kinds of reaction modes: (i) NO reaction with CO pre-treated catalyst and (ii) CO reaction with NO pre-treated catalyst, by employing in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) coupled with mass spectroscopy (MS) techniques. It was found that the generation of surface NCO complexes and N2 (g) occurs only in mode (i), which gives obvious evidence of NO dissociation over CO pre-reduced NiO/CeO2 catalyst. The result is similar to that obtained in the case of NO and CO co-adsorption, but different from that of mode (ii). The overall results indicate that CO reduction of surface oxygen should be the first and crucial step, and the dissociation of NO on the CO-reduced surface is a pathway for N2 generation. The other pathway for N2 generation is the interaction of NCO complexes with NO. Based on these understandings, we proposed reaction steps for the catalytic reduction of NO by CO over the NiO/CeO2 catalyst.
AB - Previously, we reported the prominent catalytic activity of ceria-supported nickel oxide catalyst for the reduction of NO by CO [Y. Wang, A.M. Zhu, Y.Z. Zhang, C.T. Au, X.F. Yang, C. Shi, Appl. Catal. B 81 (2008) 141-149]. In the present study, the reaction mechanism of NO and CO over the NiO/CeO2 catalyst has been examined in two kinds of reaction modes: (i) NO reaction with CO pre-treated catalyst and (ii) CO reaction with NO pre-treated catalyst, by employing in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) coupled with mass spectroscopy (MS) techniques. It was found that the generation of surface NCO complexes and N2 (g) occurs only in mode (i), which gives obvious evidence of NO dissociation over CO pre-reduced NiO/CeO2 catalyst. The result is similar to that obtained in the case of NO and CO co-adsorption, but different from that of mode (ii). The overall results indicate that CO reduction of surface oxygen should be the first and crucial step, and the dissociation of NO on the CO-reduced surface is a pathway for N2 generation. The other pathway for N2 generation is the interaction of NCO complexes with NO. Based on these understandings, we proposed reaction steps for the catalytic reduction of NO by CO over the NiO/CeO2 catalyst.
KW - DRIFTS
KW - MS
KW - NCO complexes
KW - NiO/CeO catalyst
KW - NO-CO
UR - http://www.scopus.com/inward/record.url?scp=67649265086&partnerID=8YFLogxK
U2 - 10.1016/j.apcatb.2009.03.033
DO - 10.1016/j.apcatb.2009.03.033
M3 - Article
AN - SCOPUS:67649265086
SN - 0926-3373
VL - 90
SP - 395
EP - 404
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
IS - 3-4
ER -