Electrospun silk fibroin nanofibers with fluorescent carbon quantum dots for efficient photo-degradation of environmental pollutants

Background The study investigates the use of electrospun photodynamically active carbon quantum dot (CQD) fluorescent silk for the photodegradation of environmental dye pollutants and antibacterial applications. CQDs with red, green, and blue fluorescence were synthesized from citric acid, with urea and chlorophyll as dopants. Compared to fluorescent silk obtained from silkworms fed with CQD-enriched mulberry leaves, the electrospun silk exhibits superior and stable photodegradation efficiency, making it promising for self-cleaning fabrics, antibacterial textiles, and medical dressings. Methods CQDs were synthesized using citric acid as the carbon source, doped with urea and chlorophyll to obtain different fluorescence colors. A solution containing silk fibroin, poly(ethylene oxide) (PEO), and CQDs was prepared for electrospinning to produce blue, green, and red fluorescent silk. The optical properties and quantum effects of the CQDs were analyzed using photoluminescence (PL) spectra and transmission electron microscopy (TEM), while Raman spectroscopy confirmed the presence of silk fibroin, PEO, and CQDs in the electrospun silk. Significant Findings The development of a robust and tunable electrospinning platform to fabricate multicolor fluorescent silk nanofibers incorporating CQDs. The use of environmentally friendly, aqueous-based synthesis of CQDs with sustainable dopants like chlorophyll. Enabling the photocatalytic performance under visible light. Photocatalytic degradation tests demonstrated that these fibers achieved remarkable efficiencies, with Rhodamine 6 G and Methylene Blue exhibiting degradation rates of 67 % and 75 %, respectively.