The Study Of Catalytic Mechanism For Small Noble Metal Clusters Adsorbed CO And N₂O/SO₂ Molecules

Nitrous Oxide(N2O) and Sulphur dioxide(SO2) are common air pollutant. N2 O,as one kind of Greenhouse Gas, contributing to global warming, and will destroy the ozone layer, causing the ozone hole, has become the primary human emissions of ozone-depleting substances. SO2 is the main component generating acid rain, acidifying soil, and causing other forms of air pollution, if it was not proposed properly. So it is imminent to eliminate the impact on the environment N2 O and SO2. CO as another harmful gas, often associated with N2 O and SO2 in the combustion process simultaneously. Because it is a good reducing agent. So use CO to reduce N2 O and SO2 directly into harmless gases has become a good choice. However, N2 O and SO2 in the absence of a catalyst with CO reaction requires a high temperature, it is necessary to find the appropriate catalyst, then the reaction can be carried out good.gold has high chemical stability, good mechanical properties and biocompatibility moderate, generally, gold is one kind of inert metal without catalytically active. But in nano-scale,gold nanoparticles exhibit superior catalytic performance in many important reactions. In materials science, the addition of other elements to form an alloy material will help to improve their properties. Wherein the Au-Pt binary metal particles have been extensively studied. In addition, other transition metal-doped gold clusters have also been studied. But few study to deal with these precious metal catalysts N2 O and SO2.The main contents and results of this paper are as follows: 1. Study for four negatively charged clusters PtlAum-(l+m=4) and their catalytic reaction in the conversion of N2 O and CO to N2 and CO2. By comparison of catalytic performance of different clusters, We found that Pt-Au binary clusters exhibit superior performance than pure Pt catalyst. Changing the ratio of gold atoms can reduce reaction activation barrier and avoid catalytic poisoning. 2. Research four kinds of Clusters Au3M(M=Au, Cu, Ni, Mn) and their catalytic reduction for SO2 and CO reaction. Calculation shows that gold cluster Au4 has no Catalysis in reduction of CO and SO2. However, the catalytic performance can be improved by doping atoms of other elements. In all clusters, the catalytic performance of Au3 Mn cluster is better than the others. We therefore find the ideal binary metal catalyst eliminating CO and SO2 at the same time.