초록 |
In this study, effects of selenium doping on the surface of chemically reduced graphene oxide (rGO) by simple heating with elemental selenium powders. Numerous selenium atoms were homogeneously doped on the top surface of rGOs; it caused little structural change, indicative of surface transfer doping. High resolution TEM images showed no aggregates or nanoparticles on the surface of rGOs, indicating that selenium atoms were introduced in an atomic level. Based on first-principles calculations, we found the selenium atoms to be mainly bonded to the surface edge defect sites of highly amorphorized rGO, leading to the enhancement of electrical conductivity due to n-type doping. The σ value of selenium-doped rGO (Se-rGO) reached 210 S cm–1 at 300 K, while the σ/σ20 K parameter was almost constant (1.3-fold increase from 20 to 300 K), this indicated that the carrier mobility of Se-rGO was similar to that of graphene. |