碱金属助剂对N2O直接分解催化剂NiO活性的促进作用

摘要

考察了一系列碱金属促进和未促进的NiO催化剂上N2O直接分解反应性能，并采用X射线衍射， X射线光电子能谱(XPS)和前场扫描电镜对这些催化剂进行了表征。 XPS结果表明，催化剂表面的Ni以金属颗粒， NiO和Ni(OH)2三种形式存在。研究发现，在催化剂表面主要是Ni0原子与N2O分子发生相互作用。未促进的NiO催化剂表现出非常低的催化N2O分解活性；碱金属的加入使得NiO催化剂活性大大提高。%Direct N2O decomposition has been investigated over bare NiO and a series of its alkali‐promoted catalysts. These catalysts were characterized by X‐ray diffractometry, X‐ray photoelectron spec‐troscopy (XPS) and field emission scanning electron microscopy. XPS analysis revealed that surface nickel is present in three forms:metal particles, NiO and Ni(OH)2. It is suggested that nickel(0) va‐lent atoms are essential for the interaction with N2O molecules at the catalyst surfaces. Bare NiO exhibited a very low N2O decomposition reactivity. However, the alkali‐containing catalysts exhib‐ited a marked activity enhancement.