Structural features and catalytic performance in CO preferential oxidation of CuO–CeO 2 supported on multi-walled carbon nanotubes

• Published in: Catalysis science & technology 2015, Vol.5 (3), p.1568-1579
• Main Authors: Gao, Yuxian, Xie, Kangmin, Wang, Wendong, Mi, Shiyang, Liu, Ning, Pan, Guoqiang, Huang, Weixin
• Format: Article
• Language: English
• ISSN: 2044-4753; 2044-4761
• DOI: 10.1039/C4CY01220H

Multi-walled carbon nanotube (MWCNT) supported CuO–CeO 2 catalysts were prepared using an impregnation method aided by an ultrasonication treatment. The structural features of the catalysts were extensively characterized by XRD, TGA, H 2 -TPR, XPS, TEM and Raman spectroscopy. The catalytic performance in the preferential oxidation of CO in a H 2 -rich stream was extensively investigated with respect to the influences of Cu/Ce ratios, the different support materials and the presence of CO 2 and H 2 O in the feed stream. In contrast to those supported on other materials, the catalytic performance was greatly enhanced for the MWCNT-supported CuO–CeO 2 catalysts, which was discussed in terms of the synergistic interactions between Cu–Ce mixed oxides and MWCNT. The optimized catalyst with a Cu/Ce ratio of 5/5 can achieve complete CO conversion and high selectivity toward CO 2 in a wider temperature range as well as favorable performance under the simulated reformatted gas mixture. The deactivation of CuO–CeO 2 catalysts supported on MWCNT at elevated temperatures was also discussed in relation to the temperature-dependent in situ XAFS spectra during CO-PROX reaction.