Efficient Plane-to-Point Energy Transfer from Supramolecular Excitonic Systems to Molecular Acceptors

Abstract

Collective excitonic interactions in supramolecular assemblies offer opportunities for efficient light harvesting and directed energy transport. Here, we demonstrate efficient energy transfer from two-dimensional silica-encapsulated TDBC J-aggregate sheets to covalently attached ATTO 590 molecular acceptors. Silica encapsulation preserves the J-aggregate excitonic properties while enabling acceptor functionalization at a defined separation from the donor plane. Steady-state donor quenching and acceptor sensitization yield energy-transfer efficiencies of 75-81% in solution, while time-resolved photoluminescence measurements reveal donor lifetime shortening. We develop a generalized Forster resonance energy-transfer model for an extended planar donor coupled to localized molecular acceptors, predicting an inverse fourth-power dependence of the transfer rate on donor-acceptor separation. Using experimental spectroscopic data and estimated structural parameters, the model predicts an energy-transfer rate of 4.77 x 10^10 s^-1, approximately ten times faster than the intrinsic donor decay rate, corresponding to a theoretical energy-transfer efficiency of approximately 91%. These findings provide a framework for developing hybrid excitonic architectures for light harvesting.