Density Functional Theory Analysis of Coadsorption Behavior of Cl2 and O2 on TiC (100) Surface

Based on the first -principles ab initio calculation method of density functional theory ( DFT ), the coadsorption model of Cl 2 and O 2 molecules on the TiC ( 100 ) intact surface was established. The reaction mechanism of Cl 2 and O 2 molecules on the TiC ( 100 ) intact surface was studied by analyzing adsorption energy , charge density , partial density of states ( PDOS ) and other parameters. And it was found that the dissociated Cl and O atoms bond with the TiC ( 100 ) surface atoms , thus breaking the Ti - C bond. The Cl 2 molecule acts as an electron acceptor during the adsorption process , obtaining electrons contributed by the Ti atom that bonds with it , and the O 2 molecule also acts as an electron acceptor during the adsorption process , obtaining electrons contributed by the C atom. On the surface of TiC ( 100 ), the number of electrons occupied in the bonding orbitals of Ti - C decreases , and the number of electrons occupied in the antibonding orbitals increases , which indicates the bonding between Ti and C atoms is weakened. At the same time , Ti3 d has orbital overlapping hybridization with Cl3 s and Cl3 p , and there are strong formant peaks in O2 p and C2 p orbits , and Cl and O atoms interact strongly with TiC surfaces.