摘要
采用ASED－MO量子化学方法对氮（N_2）和氛氧化合物（NO_x）在Cu、Ag、Ni、Pd、Pt5种金属（111）面上的吸附态进行了系列研究，计算结果表明：在汽车尾气净化的催化处理过程中，当用钢、银、镍、钯、铂等金属作催化剂将NO_x转化为N_2时，以金属Pt为最好。用铂作催化剂将NO还原成N_2时，可得如下反应机理：NO分子首先吸附在Pt表面，然后吸附分子NO的N－O键断裂，形成N或O原子。断裂后的吸附状态原子很容易从Pt表面脱附，而N原子也很容易结合生成N_2。
Adsorption of complexes (NO)x) on the Cu(111), Ag(111), Ni(111), Pd(111) and Pt (111) metal surfaas has been studied theoretically by using ASED-MO method. The results indicate that among the above five metals, Pt has the strongest catalytic activity for the reduction of NO_x to N_2 while purifing the tail gases, and the catalytic reaction mecanism is as follows:NO molecule is firstly adsorbed on the surfaee of Pt, then N-O bond breaks and becomes two isolated N and O atoms. These two atoms can be easily desorbed from the surface of Pt, and two free N atoms are likely to form a N_2 molecule .
关键词
催化剂
氮氧化合物
吸附
脱附
铜
银
镍
铂
钯
ASED-MO method
Metallic catalyst
N, O-containing complexes
Adsorption
Desorption
