Meanwhile, a concomitant enhancement of RhB fluorescence took place in the 580-700 nm region, which indicates an efficient energy transfer from the triplet state of the donor to the acceptor molecules (Supplementary Fig. ). The highest energy transfer efficiency reached 80.2% at 200 μg/mL RhB (Supplementary Fig. ). The time-resolved emission of the Bfibers with increased RhB content was monitored at 490 nm (λex = 270 nm): a gradual lifetime reduction was observed going from 294.03 ms to 112.78 ms (Supplementary Fig. ).