Long range energy transfer in graphene hybrid structures

In this work we quantify the distance dependence for the extraction of energy from excited chromophores by a single layer graphene flake over a large separation range. To this end hybrid structures were prepared, consisting of a thin (2 nm) layer of a polymer matrix doped with a well chosen strongly fluorescent organic molecule, followed by an un-doped spacer layer of well-defined thicknesses made of the same polymer material and an underlying single layer of pristine, undoped graphene. The coupling strength is assessed through the variation of the fluorescence decay kinetics as a function of distance between the graphene and the excited chromophore molecules. Non-radiative energy transfer to the graphene was observed at distances of up to 60 nm; a range much greater than typical energy transfer distances observed in molecular systems.We thank Nuno Peres and Bruno Amorim for informative discussions. This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project PEST-C/FIS/UI607/2011 and under grant PTDC/FIS/101434/2008. TS has been supported by Spain’s MINECO under Grant No. FIS2014-57432-P and by the Comunidad de Madrid under Grant No. S2013/MIT-3007 MAD2D-CM