Natural ultralong hemicelluloses phosphorescence

Artificial materials exhibiting ultralong organic phosphorescence (UOP), especially those with tunable multicolor afterglow, are hindered by complicated synthesis and purification, poor processability, and issues relating to sustainability. Here, we report natural hemicelluloses that provide excitation- and time-dependent color-tunable afterglow. In particular, linear xylan with high crystallinity exhibits a long lifetime of 588.8 ms under ambient conditions, not inferior to many artificial phosphors, and has achieved industrial production. Mechanistic study shows that the tunable UOP can be ascribed to various clusters of oxygen groups fixed within a rigid polysaccharide environment. The distinguishable color evolution and duration of afterglow are useful for anticounterfeiting and data encryption with high security levels. Furthermore, body-shaped foams with a lifetime up to approximately 700 ms and flexible, transparent, and high-strength phosphorescence film can also be fabricated using water-soluble oxidized xylan. These results unambiguously state that hemicellulose-based UOP materials are convincingly promising to replace and surpass artificial phosphors.