Energy Transfer from Dual-Emission Manganese-Doped Quantum Dots to Graphene Oxide

The combination of doped quantum dots (QDs) and graphene oxide (GO) results in QD-GO composites with enhanced light absorption properties. When exposed to light, the dual-emission Mn2+-doped ZnS QD-GO composite exhibits nonradiative energy transfer from photoexcited QDs to GO. Using steady-state spectroscopy and time-resolved spectroscopy, we find that the energy transfer efficiency between QDs' surface defects and GO is higher than that between isolated Mn2+ ions and GO. Moreover, the increase of GO concentration and reduction degree can improve the electron population of defect states of QDs, while the electron population in Mn2+ ions is relatively less affected by GO. This study leads to a better understanding of the energy transfer dynamics between dual-emitting Mn2+-doped ZnS QDs and GO and should greatly contribute to the design of high-performance QD-based optoelectronic devices.