【摘要】 用TDS和AES考察了CO在多晶Ni上的Sm膜和Sm/Ni表面合金上的吸附与反应.CO可氧化Sm而生成Sm₂O_x和表面碳,后者可在约1000K的高温下与Sm₂O_x中的氧重新并合而产生CO高温脱附峰.CO在Sm/Ni表面合金上的吸附引起表面合金结构的破坏,造成Sm₂O_x在表面的偏析和聚集,使热脱附谱和多晶Ni相近.预吸附在Sm/Ni合金表面上的CO可以被后吸附的氧取代;而预吸附在相同表面上的氧却使CO的后吸附强烈受阻.化学吸附的氧和CO解离生成的表面碳之间的反应,使热脱附谱中600～800K的中间温度区出现新的CO脱附峰.更多还原

【Abstract】 The adsorption and reaction of CO on the Sm overlayer and Sm/ Ni alloy surfaces have been investigated with TDS and AES. The CO is adsorbed dissociatively on Sm overlayer. and can oxidize Sm to form SmOx and surface carbon which associatively desorb at high temperature of - 1000K. CO adsorption on Sm/Ni surface alloys leads to disruption of alloy phase and induces the segregation and aggregation of Sm2Ox on the surface. The corresponding TD spectrum of CO appears to be similar to that observed on clean Ni surface. The CO preadsorbed on Sm Ni surface alloy can be displaced by oxygen, while the preadsorbed oxygen completely suppress any further uptake of CO.更多还原