Alloy-Mediated Ultra-Low CO Selectivity for Steam Reforming over Cu−Ni Bimetallic Catalysts

Graphical Blowing off steam : This paper describes a new approach of designing Cu−Ni bimetallic catalytic systems for dimethyl ether/methanol steam reforming. The Cu−Ni system exhibits an interesting alloy-mediated selectivity of CO and CH 4 , thereby producing hydrogen-rich reformates with an ultra-low CO concentration (<1000 ppm), which could be commercially potential for fuel cells. Steam reforming of simple oxygenated hydrocarbons without C−C bonds is suitable for small-scale decentralized H 2 production for fuel cells. However, the relatively high CO concentration in H 2 -rich reformates produced by traditional Cu-based catalysts will poison the Pt-based anode in fuel cells. Here, we describe a new approach to the design of Cu−Ni bimetallic catalysts based on nickel-phyllosilicate for steam reforming of dimethyl ether (DME). With the tunable formation of the Cu−Ni alloy, we can modulate the selectivity of CO and CH 4 in steam reforming and achieve H 2 -rich reformates with an ultra-low concentration of CO (below 1000 ppm). This process only requires simple and low-energy purification pretreatments to meet the requirements of commercial fuel cells. Mechanistic studies reveal that the Cu−Ni alloy can adsorb CO, particularly at high temperatures, and simultaneously suppress CO dissociation to methane.