Self-assembled flower like superstructures of highly emitting InP/ZnSe/ZnS quantum dots

Superstructure with emitting Quantum Dots (QD) as building blocks can bring new avenues to rational design in the synthesis of desired QD based functional materials with novel optical properties. Here we report one pot colloidal synthesis of self assembled flower like superstructures from InP/ZnSe/ZnS QDs having yellow emission with photoluminescence quantum yield (PLQY) of 87 %. Such highly emissive quantum dot-based superstructures were achieved through meticulous selection of surface-capping ligands and engineering of surface chemistry. Here, tri-octyl-phosphine (TOP) plays a key role in formation of the flower like superstructures and improving the optical properties, which was further investigated theoretically through first principle calculations. The superstructures obtained are structurally and optically stable for long periods of time. The heavy metal free highly emitting InP based QD's size and composition tunability and their ability of forming superstructures will be highly beneficial for development of new solution processable building blocks for QD based superstructures with superior and well controlled physical, optical and chemical properties. The synthesized InP based yellow emitting nanostructures, will certainly be a promising candidate for the development of non-toxic QD based devices in optoelectronics, plasmonics and catalysis. Quantum dots offer promising pathways for designing functional materials with novel optical properties. Here, the authors present colloidal synthesis of flower-like self-assembled InP/ZnSe/ZnS superstructures with remarkable photoluminescence quantum yield, paving the way for non-toxic, highly stable quantum dot devices in optoelectronics and catalysis.