| 초록 |
The heterojunction structures of layered materials are currently being studied a lot as an electrode of a rechargeable SIB. Among them, it is experimentally known that MoS2/rGO has higher capacity and lower electric conductivity than MoS2/Graphene due to the functional group. However, underlying mechanism for such an impact has not yet been clearly identified. In this study, the effect of functional groups on capacity and electrical conductivity, which are important indicators for performance of electrodes, and their mechanisms were decoupled to individual functional groups to investigate using the first-principles density functional theory computation. Through ab-initio thermodynamics calculation and electronic structure analysis, it was confirmed that the Na intercalation energy was lowered in the order of O, COOH, and OH, which implies elevated capacity, but the electrical conductivity was lowered. Our study can provide theoretical guidelines for future development of high-performance electrodes through atomistic level understanding on the relationship between the functional groups in graphene and the performance of electrode. |
