Synergetic Effect Of Copper Cerium Catalyst Promoted By Honeycomb-like Porous Carbon In Response For CO-PROX Performance

Hydrogen has been considered as the cleanest secondary energy source,and proton exchange membrane fuel cells（PEMFCs）is one of the important applications of hydrogen energy.However,a small amount of CO in the hydrogen gas will poison the PEMFCs electrode,and the CO content must be reduced to below 100 ppm in order for the battery to operate normally.The preferential oxidation of carbon monoxide（CO-PROX）is the most effective method to removal CO from hydrogen.Due to the large particle size and low concentration of defects in the traditional CuO-CeO₂catalysts,the catalytic activity at the low temperature is not ideal.Honeycomb-like carbon materials has attracted attention due to its high specific surface area,good conductivity,and large diffusion channels.In this paper,the honeycomb-shaped carbon material（HPC）was selected as the carrier to support the Cu_xO-CeO₂ composite oxides,and Cu_xO-CeO₂/HPC catalysts with different molar ratios of Cu/Ce were applied to the CO preferentially oxidize reaction.The effect of the HPC on the catalytic performance was studied.The specific research as follows:A series of the Cu_xO-CeO₂/HPC,Cu_xO/HPC,CeO₂/HPC and CuO-CeO₂ catalysts with different Cu/Ce were prepared by hydrothermal method.It is found that honeycombed carbon materials increased the number of highly dispersed copper and high concentration of oxygen vacancies,and reduced the size of CeO₂ and Cu_xO particles,The special three-dimensional structure of HPC prevents the agglomeration of CeO₂ and Cu_xO and therefore exposes more active sites.The synergy of CeO₂ and Cu_xO enhances the catalytic activity of CO-PROX reaction.A series of the Cu_xO-CeO₂/HPC and CuO-CeO₂ catalysts with different Cu/Ce wereprepared by impregnation method.It is found that when the molar ratio of Cu/Ce is 1:2,the activity of CO-PROX is the best.The effects of Cu_xO-CeO₂/HPC prepared by impregnation and hydrothermal methods on the different effects of CO-PROX were compared through a series of characterizations.It is found that the Cu_xO-CeO₂/HPC catalyst prepared by hydrothermal methods has higher Ce³⁺concentration and oxygen vacancy concentration,and the PROX performance at the low temperature is better than the former.