PdZn/Pd(111) surface alloys as model catalysts for methanol steam reforming
نویسندگان
چکیده
Pd supported on ZnO has recently raised great interest as a catalyst for methanol steam reforming. Different from unsupported Pd, Pd-ZnO shows high selectivity and good conversion towards CO2 and hydrogen [1]. The difference is attributed to the formation of a PdZn alloy under reaction conditions, but there is still limited knowledge on the exact surface structure/composition and reaction mechanism(s). To get further insight, we have investigated the adsorption and interaction of CO and methanol with a well-defined model PdZn/Pd(111) 1:1 surface alloy, using XPS (X-ray Photoelectron Spectroscopy) and PM-IRAS (Polarization-Modulation IR Reflection Absorption Spectroscopy).
منابع مشابه
Where does methanol lose hydrogen to trigger steam reforming? A revisit of methanol dehydrogenation on the PdZn alloy model obtained from kinetic Monte Carlo simulations.
Pd/ZnO is a promising catalyst studied for methanol steam reforming (MSR) and the 1 : 1 PdZn alloy is demonstrated to be the active component. It is believed that MSR starts from methanol dehydrogenation to methoxy. Previous studies of methanol dehydrogenation on the ideal PdZn(111) surface show that methanol adsorbs weakly on the PdZn(111) surface and it is hard for methanol to transform into ...
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