Study of alloyed quantum dots-porphyrazine interaction in solution

Abstract The core-shell quantum dots, namely, CdSxSe1-x/ZnS (QD), and free-base porphyrazine (1) undergoes spontaneous interaction in solution. Steady state fluorescence measurements reveal significant quenching of the photoluminescence of QD in presence of 1. The average value of lifetime of QD (16.10 ns) suffers negligible change in presence of 1 (15.55 ns). The value of bimolecular quenching constant, i.e., kq for QD-1 system (kq = 1.380 × 1011 l·mol−1·s−1) determined from time-resolved fluorescence experiment rules out the possibility of diffusion driven process in present work. The mechanism of binding interaction between QD and 1 is established following the evaluation of binding constant value, i.e., K = 12,720 l·mol−1 for QD-1 system. The results emanating from present work would be very much helpful for employing QD-porphyrazine type system as possible binding unit in energy and/electron transfer process.