Quantum dot-organic semiconductor hybrid materials are gaining increasing attention as spin mixers for applications ranging from solar harvesting to spin memories. Triplet energy transfer between the inorganic quantum dot (QD) and organic semiconductor is a key step to understand in order to develop these applications. Here we report on the triplet energy transfer from PbS QDs to four energetically and structurally similar tetracene ligands. Even with similar ligands we find that the triplet energy transfer dynamics can vary significantly. For TIPS-tetracene derivatives with carboxylic acid, acetic acid and methanethiol anchoring groups on the short pro-cata side we find that triplet transfer occurs through a stepwise process, mediated via a surface state, whereas for monosubstituted TIPS-tetracene derivative 5-(4-benzoic acid)-12-triisopropylsilylethynyl tetracene (BAT) triplet transfer occurs directly, albeit slower, via a Dexter exchange mechanism. Even though triplet transfer is slower with BAT the overall yield is greater, as determined from upconverted emission using rubrene emitters. This work highlights that the surface-mediated transfer mechanism is plagued with parasitic loss pathways and that materials with direct Dexter-like triplet transfer are preferred for high-efficiency applications.
|Number of pages||9|
|Journal||Journal of Materials Chemistry C|
|State||Published - Oct 11 2022|
Bibliographical noteFunding Information:
We thank the Winton Programme for the Physics of Sustainability and the Engineering and Physical Sciences Research Council (Grant EP/P027741/1) for funding. This project has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement no. 758826). VG acknowledges funding from the Swedish research council, Vetenskapsrådet 2018-00238. J. R. A. acknowledges Cambridge Commonwealth European and International Trust for financial support. Z. Z. acknowledges funding from the European Union's Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Actions grant (no. 842271 – TRITON project). J. X. acknowledges EPSRC Cambridge NanoDTC, EP/L015978/1 for financial support. D. G. C. acknowledges the Herchel Smith fund for a postdoctoral fellowship. JEA acknowledge the US National Science Foundation under cooperative agreement no. 1849213, for support of organic semiconductor synthesis.
© 2022 The Royal Society of Chemistry.
ASJC Scopus subject areas
- Chemistry (all)
- Materials Chemistry