Hyperbranched polymers (HBPs) with decorated donor and acceptor chromophores in different domains were constructed to demonstrate the function of light harvesting in a polymeric nanostructure. Taking advantage of our recently developed chain‐growth copper‐catalyzed azide–alkyne cycloaddition polymerization, two structural parameters in the HBPs, for example, the molar ratio of the acceptor Coumarin 343 in the core to the donor Coumarin 2 on the periphery, and the average distance between these two layers, could be independently varied in a one‐pot synthesis. The results demonstrated an efficient energy transfer from the excited Coumarin 2 to the ground‐state Coumarin 343 in the core, with the efficiency of the energy transfer reaching as high as 98 %. The excited Coumarin 343, after receiving energy from donor Coumarin 2 emitted higher fluorescence intensity than when directly excited, indicating an observed light concentration effect from the periphery dye to the central dye in one polymer structure.
- Award ID(s):
- 1904631
- PAR ID:
- 10322888
- Date Published:
- Journal Name:
- Polymer Chemistry
- Volume:
- 12
- Issue:
- 31
- ISSN:
- 1759-9954
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Hyperbranched polymers (HBPs) with decorated donor and acceptor chromophores in different domains were constructed to demonstrate the function of light harvesting in a polymeric nanostructure. Taking advantage of our recently developed chain‐growth copper‐catalyzed azide–alkyne cycloaddition polymerization, two structural parameters in the HBPs, for example, the molar ratio of the acceptor Coumarin 343 in the core to the donor Coumarin 2 on the periphery, and the average distance between these two layers, could be independently varied in a one‐pot synthesis. The results demonstrated an efficient energy transfer from the excited Coumarin 2 to the ground‐state Coumarin 343 in the core, with the efficiency of the energy transfer reaching as high as 98 %. The excited Coumarin 343, after receiving energy from donor Coumarin 2 emitted higher fluorescence intensity than when directly excited, indicating an observed light concentration effect from the periphery dye to the central dye in one polymer structure.
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