Adsorption of molecular oxygen on Ti-doped monolayer MoS₂ and effect of applied electric field: A DFT study

It is proposed that by tuning the O₂ adsorption on Ti-doped MoS₂, the resulting materials system can be used as nanocatalyst. To this end, density functional theory calculations was first performed to study the adsorption of molecular oxygen on pristine MoS₂ and Ti-doped MoS₂. It was found that O₂ molecule adsorption energy on pristine MoS₂ was very weak. However, the adsorption of O₂ molecule on monolayer Ti-doped MoS₂ shows relatively higher affinity. The results showed that the Ti-bridge-O₂ configuration is most stable. The analysis of molecular projected density of state and charge transfer indicates that the interaction between the O₂ molecule and the Ti dopant is chemisorption via two Ti-O bonds, which affects the magnetic, electronic, and atomic properties of Ti-doped MoS₂. Furthermore, the adsorption energy and O-O distance of Ti-doped MoS₂ under electric field have been studied. It is hoped that together with electric field, the tuned O₂ adsorption on Ti-doped MoS₂ could become a nanocatalyst.