(Carrière) J. Houz) were demonstrated for their tunability (Fig. and Supplementary Fig. ). Particularly, the RTP lifetime decreased from 757.3 ms to 39.2 ms when the temperature increased from 77 K to 400 K. Such temperature-dependent RTP emission is explained by nonradiative migration of triplet excitons promoted at high temperatures. Additionally, the B-fibers exhibited quenched RTP emission when exposed to humid environments (Supplementary Fig. ). Specifically, the RTP lifetime decreased from 294.9 ms to 19.8 ms when the humidity increased from 0% to 90%. Interestingly, the lifetime was recovered by drying the wet B-fibers.