Microwave-assisted one-pot synthesis of hybrid nanosystems based on CdS quantum dots functionalized with organic chromophores: effect of the chromophore nature on the nanosystem composition†
A novel method of one-pot microwave assisted synthesis was employed to prepare hybrid nanosystems (HNSs) with CdS quantum dots (QD) covered by an organic shell containing capping “background” ligand (benzylmercaptan, BM) and functional ligand (FL) with a styrylquinoline (SQ) or merocyanine (MC) chromophore group. An average amount (n) of the FL molecules in the HNS organic shell was measured. We herein report on an unusual dependence of n on the FL relative concentration in the source solution. A non-linear dependence resembling a cooperative effect is found for the SQ-FL, and a linear dependence with critical concentration is found for the MC-FL. The effects are suggested to be associated with the peculiarities of microwave activation of the ligands, which are built into the organic shell of the HNS as a result of a kinetically rather than thermodynamically controlled process. These data shed light on the problem of the formation of the covering organic shell on the QD surface in different conditions.