Distance Dependence of the Energy Transfer Rate From a Single Semiconductor Nanostructure to Graphene

TL;DR

This study investigates how the energy transfer rate from individual semiconductor nanostructures to graphene varies with distance, revealing different decay behaviors for zero-dimensional nanocrystals and two-dimensional nanoplatelets, with implications for nanoscale measurements.

Contribution

It provides the first detailed analysis of distance-dependent energy transfer from single nanostructures to graphene, including a theoretical model for nanoplatelets.

Findings

Nanocrystals exhibit a $1/d^4$ decay in energy transfer rate.

Nanoplatelets' energy transfer deviates from simple power law, fitting a theoretical model.

Graphene-based molecular rulers enable precise nanoscale distance measurements.

Abstract

The near-field Coulomb interaction between a nano-emitter and a graphene monolayer results in strong F\"orster-type resonant energy transfer and subsequent fluorescence quenching. Here, we investigate the distance dependence of the energy transfer rate from individual, i) zero-dimensional CdSe/CdS nanocrystals and ii) two-dimensional CdSe/CdS/ZnS nanoplatelets to a graphene monolayer. For increasing distances $d$, the energy transfer rate from individual nanocrystals to graphene decays as $1/d^4$. In contrast, the distance dependence of the energy transfer rate from a two-dimensional nanoplatelet to graphene deviates from a simple power law, but is well described by a theoretical model, which considers a thermal distribution of free excitons in a two-dimensional quantum well. Our results show that accurate distance measurements can be performed at the single particle level using graphene-based molecular rulers and that energy transfer allows probing dimensionality effects at the nanoscale.