CH4 dissociation on Co（0001） surfaces is an important step, which has been investigated at the level of density functional theory. It is found that CH4 is unfavorable to adsorb on Co（0001）, while CH4 favores to di...CH4 dissociation on Co（0001） surfaces is an important step, which has been investigated at the level of density functional theory. It is found that CH4 is unfavorable to adsorb on Co（0001）, while CH4 favores to dissociate to CH3, CH2 and CH on Co（0001） surface by sequential dehydrogenation. In the whole process of CH4 dehydrogenation, CH4 dissociate to CH3 and H is the rate-determining step. The calculated results show that CH2 and CH exist mainly on Co（0001） surface, while the dehydrogenation of CH into C and H is difficult.展开更多
The electrooxidation of CO on Ru (0001) and RuO2 (100) electrode surfaces were characterized by cyclic voltammetry, AES and RHEED. The CO adlayer was first partially oxidized at 0.8 V, which is controlled by the atta...The electrooxidation of CO on Ru (0001) and RuO2 (100) electrode surfaces were characterized by cyclic voltammetry, AES and RHEED. The CO adlayer was first partially oxidized at 0.8 V, which is controlled by the attack of oxygen species toward the Ru(0001) surface. The remaining CO adlayer oxidation at 0.55 V is related to the combination of CO molecules with oxygen species already located on the surface. In contrast, successive peaks on RuO2(100) at 0.4 V and 0.72 V are observed, which shows that CO molecules can directly react with two different lattice-oxygen on the surface to carbon dioxide.展开更多
文摘CH4 dissociation on Co（0001） surfaces is an important step, which has been investigated at the level of density functional theory. It is found that CH4 is unfavorable to adsorb on Co（0001）, while CH4 favores to dissociate to CH3, CH2 and CH on Co（0001） surface by sequential dehydrogenation. In the whole process of CH4 dehydrogenation, CH4 dissociate to CH3 and H is the rate-determining step. The calculated results show that CH2 and CH exist mainly on Co（0001） surface, while the dehydrogenation of CH into C and H is difficult.
文摘The electrooxidation of CO on Ru (0001) and RuO2 (100) electrode surfaces were characterized by cyclic voltammetry, AES and RHEED. The CO adlayer was first partially oxidized at 0.8 V, which is controlled by the attack of oxygen species toward the Ru(0001) surface. The remaining CO adlayer oxidation at 0.55 V is related to the combination of CO molecules with oxygen species already located on the surface. In contrast, successive peaks on RuO2(100) at 0.4 V and 0.72 V are observed, which shows that CO molecules can directly react with two different lattice-oxygen on the surface to carbon dioxide.
