Scalable Industrial Production of Bio-Based Lignin-Activated Room Temperature Phosphorescent Fibers

Room temperature phosphorescence (RTP) fibers derived from natural sources exhibit great potential, but their large-scale preparation remains challenging. This work overcomes this major bottleneck by demonstrating the first successful large-scale manufacturing of bio-based, room temperature phosphorescent (RTP) fibers. By integrating lignin, an abundant biopolymer, directly into a commercial viscose fiber production line, we have developed a cost-effective process to produce high-performance phosphorescent viscose (PV) fibers at an industrial scale. The process employed key industrial parameters, including a coagulation bath temperature of 49°C, and a lignin incorporation rate of 1% (w/w) relative to cellulose, with continuous filament collection. These monolithic fibers exhibit a robust and long-lived green afterglow (lifetime of 217.5 ms) and exceptional mechanical strength (629.2 MPa), properties imparted by the unique Cellulose II matrix formed during the industrial co-regeneration process. Moreover, the wavelength of PV-fiber is tunable, ranging from 500 to 520 nm, by changing the excitation wavelength and using an energy transfer strategy. To prove their immediate viability, the PV-fibers are seamlessly processed into yarns and textiles using standard machinery, creating advanced multi-level anti-counterfeiting embroidery and luminescent surgical sutures. This breakthrough provides a direct and tangible pathway from renewable biomass to the mass production of advanced luminescent fabrics, paving the way for their integration into consumer and biomedical products.