New paper online in ACS Energy Letters on energy transfer in halide perovskite nanoplatelets
A new manuscript of ours has been accepted for publication in ACS Energy Letters: Nonradiative energy transfer between thickness-controlled halide perovskite nanoplatelets by Andreas Singldinger and others from the Nanospectroscopy Group!
Despite showing great promise for optoelectronics, the commercialization of halide perovskite nanostructure-based devices is hampered by inefficient electrical excitation and strong exciton binding energies. While transport of excitons in an energy-tailored system via Förster resonance energy transfer (FRET) could be an efficient alternative, halide ion migration makes the realization of cascaded structures difficult. Here, we show how these could be obtained by exploiting the pronounced quantum confinement effect in two-dimensional CsPbBr3-based nanoplatelets (NPls). In thin films of NPls of two predetermined thicknesses, we observe an enhanced acceptor photoluminescence (PL) emission and a decreased donor PL lifetime. This indicates a FRET-mediated process, benefitted by the structural parameters of the NPls. We determine corresponding transfer rates up to kFRET = 0.99 ns-1 and efficiencies of nearly ηFRET = 70 %. We also show FRET to occur between perovskite NPls of other thicknesses. Consequently, this strategy could lead to tailored, enery cascade nanostructures for improved optoelectronic devices.
Read more at ACS Energy Letters!