Room Temperature Phosphorescent Nanofiber Membranes by Bio‐Fermentation

Abstract Stimuli‐responsive materials exhibiting exceptional room temperature phosphorescence (RTP) hold promise for emerging technologies. However, constructing such systems in a sustainable, scalable, and processable manner remains challenging. This work reports a bio‐inspired strategy to develop RTP nanofiber materials using bacterial cellulose (BC) via bio‐fermentation. The green fabrication process, high biocompatibility, non‐toxicity, and abundant hydroxyl groups make BC an ideal biopolymer for constructing durable and stimuli‐responsive RTP materials. Remarkable RTP performance is observed with long lifetimes of up to 1636.79 ms at room temperature. Moreover, moisture can repeatedly quench and activate phosphorescence in a dynamic and tunable fashion by disrupting cellulose rigidity and permeability. With capabilities for repeatable moisture‐sensitive phosphorescence, these materials are highly suitable for applications such as anti‐counterfeiting and information encryption. This pioneering bio‐derived approach provides a reliable and sustainable blueprint for constructing dynamic, scalable, and processable RTP materials beyond synthetic polymers.