Functionalized Molybdenum Disulfide Nanosheets for 0D-2D Hybrid Nanostructures: Photoinduced Charge Transfer and Enhanced Photoresponse.

The high-concentration stable dispersion of free-standing mono- or few-layer transition metal dichalcogenide (TMD) nanosheets (NSs) remains a significant barrier for their application in solution-processed optoelectronic devices. Here, we report oleylamine (OLA)- and dodecanethiol (DDT)-assisted exfoliation of MoS2 NSs in nonpolar organic solvent 1,2-dichlorobenzene (DCB), which enables high-concentration stable dispersion of free-standing mono- or few-layer NSs. The functionalized MoS2 NSs were further utilized for the fabrication of solution-processed 0D-2D hybrids of CuInS2 quantum dots (CIS QDs) and MoS2 NSs. The strong photoluminescence (PL) quenching and decreased PL lifetimes of CIS QDs attached to MoS2 NSs indicates efficient charge transfer from photoexcited CIS to MoS2 NSs. The photocurrent of CIS/MoS2 hybrid devices is dramatically enhanced compared to that of pure CIS and pristine MoS2-based devices, confirming that efficient charge separation and transfer occur from CIS QDs to MoS2 NSs.