| Nowadays, selective catalytic reduction （SCR） is widely used for removal of nitrogenoxides emitted from power plants. Because of the low-temperature catalytic of Manganesemixed oxide, it is a good SCR catalyst. The simulation of suface adsorption has importanteconomic and practical significance to develop new low-temperature catalyst. The bandstructure, Desity of states and the adsoption of NO on MnO（001） surface has been studied inthis thesis.In this thesis, we introduced the development and application of computationalsimulation method that applied in catalysis research field. Some important concepts, such asbeyond Density Functional Theory （DFT+U）, Generalized Gradient Approximation （GGA）,Local Density Approximation （LDA）, have been explained. The function and application ofCASTEP, Gaussian03and VASP software pack also has been presentsd.MnO crystal is strongly correlated systems with3d electrons, and it has a good catalyticproperties. Here we used the CASTEP modules of Material studio software to calculate thedensity of states with the DFT+U. Studies have shown that the method improved significantlythe agreement between theoretical and experimental results. Here we identified the HubbardU parameter and get the good density of states. When UMn,d=10.3eV and UO,p=6.5ev, the bandgap of MnO is3.65ev, and it is closely to experimental results. Otherwise the DOS of FeOhas been calculated with DFT+U by VASP software. The comparison on DOS and crystalconstant between theoretical and experimental results told us that the DFT+U and B3LYPfunction can calculate the electronic structure and the density of state of strongly correlatedoxide.In this thesis, the adsorption of NO on MnO（001） surface with Dmol3and cluster modelhas been calculated.Dmol3results show that NO adsorb on MnO（001） wit N-Down structure,and the binding energy is bigger. The cluster model with Mn5O5results show that NO alsoadsorb on MnO（001） wit N-Down structure. |
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