Fabrication of Stacked MoS₂ Bilayer with Weak Interlayer Coupling by Reduced Graphene Oxide Spacer

We fabricated the stacked bilayer molybdenum disulfide (MoS₂) by using reduced graphene oxide (rGO) as a spacer for increasing the optoelectronic properties of MoS₂. The rGO can decrease the interlayer coupling between the stacked bilayer MoS₂ and retain the direct band gap property of MoS₂. We observed a twofold enhancement of the photoluminescence intensity of the stacked MoS₂ bilayer. In the Raman scattering, we observed that the E¹_2g and A_1g modes of the stacked bilayer MoS₂ with rGO were further shifted compared to monolayer MoS₂, which is due to the van der Waals (vdW) interaction and the strain effect between the MoS₂ and rGO layers. The findings of this study will expand the applicability of monolayer MoS₂ for high-performance optoelectronic devices by enhancing the optical properties using a vdW spacer.