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

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 CH4 in steam reforming and achieve H-2-rich reformates with an ultra-low concentration of CO (below 1000ppm). 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.