First Principle Study on Mn-Doped Ceria with Different Doping Concentration

First-principle software bundle based on the density functional theory (DFT) is used to investigate pure CeOB2B and Mn-doped CeOB2B with different doping concentration. The structural model of CeOB2B crystal is constructed and geometrically optimized, the electron density of states and band structure calculated. The results are as follows: the valence band top of CeOB2B is made up with O2p and Ce5d states, and the existence of 4f unoccupied molecular orbital of CeOB2B facilitates the electronic storage. The theoretical calculation models of Mn-doped CeOB2B with different concentration are constructed and calculated, including 2*1*1, 2*2*1 and 2*2*2 supercell models. After CeOB2B is doped, hybridization happens between 4s orbitals of Mn atoms and 2p orbital of O atoms, resulting in 4s orbitals of Mn atoms lose electrons.Moreover, Mn atom is electron donor and O atoms is the electron acceptor. As the doping concentration decreases, the formation energy also decreases.And a smaller formation energy leads to a more stable structure.