Electrostatics enable resonance energy transfer in all-InP quantum dot containing donor-acceptor assembly

Abstract

Light-harvesting studies in donor-acceptor nanohybrid systems based on all-environmentally friendly quantum dots (QDs) are necessary to realize their applications in energy and medical research. Here, we demonstrate an efficient F & ouml;rster resonance energy transfer (FRET) process in an electrostatically bound all-QD based assembly comprised of indium phosphide/zinc sulfide (InP/ZnS) QDs as both the donor and the acceptor. A perfect control on the speed of nucleation and growth steps, along with appropriate surface functionalization with oppositely charged ligands, enabled an electrostatically bound all-QD donor-acceptor nanohybrid assembly comprising of green- and red-emitting InP/ZnS QDs. Detailed spectroscopic studies revealed the importance of electrostatic attraction in accomplishing an efficient FRET process (similar to 75%) from donor [+] G-InP/ZnS QDs to acceptor [-] R-InP/ZnS QDs. Further, solid-state studies helped in visualizing the distance-dependent nature of the FRET process at a fixed donor-acceptor ratio. The all-InP QD containing donor-acceptor nanohybrid assembly developed here could find applications in other light-harvesting studies as well, including photovoltaics and photocatalysis.