Photoluminescence Enhancement  of Aluminum Ion Intercalated MoS₂ Quantum Dots

Low photoluminescence (PL) quantum yield of molybdenum disulfide (MoS₂) quantum dots (QDs) has limited practical application as potential fluorescent materials. Here, we report the intercalation of aluminum ion (Al³⁺) to enhance the PL of MoS₂ QDs and the underlying mechanism. With detailed characterization and exciton dynamics study, we suggest that additional surface states including new emission centers have been effectively introduced to MoS₂ QDs by the Al³⁺ intercalation. The synergy of new radiative pathway for exciton recombination and the passivation of non-radiative surface traps is responsible for the enhanced fluorescence of MoS₂ QDs. Our findings demonstrate an efficient strategy to improve the optical properties of MoS₂ QDs and are important for understanding the regulation effect of surface states on the emission of two dimensional sulfide QDs.