【摘要】 利用XPS对以金属盐共浸渍制备的PH+CO/AL₂O₃和RH₂Co₂（CO）₁2为前体制备的Rh₂Co₂/Al₂O₃催化剂的金属-金属及金属-载体相互作用进行了详细的研究.发现Rh+Co/Al₂O₃经400℃ H₂还原后RH的结合能与Rh⁰的结合能接近,Co基本上以CoAL₂O₄状态存在,Co₀的谱峰很弱;而Rh₂Co₂/Al₂O₃经400℃H₂还原后Rh的结合能与Rh⁰接近,Co除以CoAl₂O₄状态存在外,还有相当一部分以Co⁰状态存在.上述结果揭示出两个样品的RH-Al₂O₃的相互作用弱,Co-Al₂O₃的相互作用强.Rh+Co/Al₂O₃上Rh-Co相互作用弱,而Rh₂Co₂/Al₂O₃在H₂还原后仍保持RhCo簇合物的强的Rh-Co相互作用,导致显著量的Co⁰存在.更多还原

【Abstract】 Metal - metal and metal - support interaction on Rh + Co/Al2O3 prepared by co -impregnation and Rh2Co2/Al2O3 by using RhCo carbonyl cluster as the precusor have been studied in detail by X - ray Photoelectron Spectroscopy(XPS). It was found that binding energy for Rh3d on Rh + Co/Al2O3 reduced with H2 at 400℃ is nearly identical with that of Rh0, and Co exists essentially in CoAl2O4 state and only the very small amount of Co exists as Co0. On Rh2Co2/Al2O3 reduced with H2 at 400℃ Rh exists as Rh0, and a part of Co exists in CoAl2O4 state whereas another part of Co exists as Co0. Results above indicate that Rh - A12O3 interaction for Rh + Co/Al2O3 and Rh2Co2/Al2O3 is weak, and Co - Al2O3 interaction is strong; Rh - Co interaction on Rh + Co / Al2O3 prepared by coimpregnation of RhCl3 and Co ( NO3)2 is weak , but on Rh2Co2/Al2O3 prepared by using RhCo carbonyl cluster as the precusor the strong Rh -Co interaction of RhCo carbonyl cluster is still maintained resulting in the considerable amount of Co0更多还原