Study of complexation and energy transfer phenomenons in core/shell quantum dots-tetraphenyl porphyrin systems in solution

Free-base tetraphenyl porphyrin (H 2 TPP) undergoes spontaneous interaction with CdSe/ZnS (core/shell) quantum dots (C/S QD) having a diameter of 5 to 10 nm in solution. Fluorescence measurements show that C/S QD suffers a considerable extent of photoluminescence quenching at 612 nm due to the formation of the C/S QD-H 2 TPP complex. The formation of C/S QD-H 2 TPP self-assembly is quantified by evaluating such system’s association constant (K), i.e., K C/S QD-H2TPP ∼ 4.0 × 10 5 dm 3 /mol. The value of the bimolecular quenching constant (k) of the C/S QD-H 2 TPP system (k C/S QD-H2TPP ) is estimated to be ∼ 5.47 × 10 12 dm 3 /mol.sec, which signifies the role of static quenching in present work. Photophysical parameters obtained from this work may be suitably utilized for the future application of the C/S QD-H 2 TPP system in energy storage units.