Multi-wall carbon nanotubes as support of copper-cerium composite for preferential oxidation of carbon monoxide

The CuxO/MWCNTs, CeO2/MWCNTs and CuxO-CeO2/MWCNTs catalysts were synthesized by a simple impregnation method, and characterized via X-ray diffraction, N-2 adsorption-desorption, Fourier transformed infrared spectroscopy, transmission electron microscopy, H-2 temperature-programmed reduction and X-ray photoelectron spectra. The catalytic performance for preferential CO oxidation was carried out in the hydrogen-rich gasses. It is found that the hydrophilic functional groups of hydroxyl and carboxyl in the samples are favorable for the incorporation of CuxO and CeO2 into the tubes of the MWCNTs. Most of CuxO particles and CeO2 nanowires are filled in the tubes of MWCNTs, and a small amount of nanoparticles are deposited on the surface of MWCNTs. The MWCNTs have high BET surface area, which is helpful for the dispersion of CuxO and CeO2 to expose more active surface for CO-PROX reaction over the CuxO-CeO2/MWCNTs catalysts. The CuxO-CeO2/MWCNTs-C catalyst shows good catalytic activity and the temperature window of CO total conversion is from 135 degrees C to 175 degrees C. MWCNTs with high BET surface area weaken poisoning effect of H2O and CO2 after 135 degrees C. (C) 2015 Elsevier B.V. All rights reserved.