Functionalization of Cotton Fabric with Carbon Dots for Multifunctional Applications

We report a groundbreaking textile modification strategy utilizing fluorescent whitening carbon dots (FW-CDs) to simultaneously achieve multifunctional performance while maintaining fabric comfort. Through controlled hydrothermal synthesis of traditional VBL precursor, bright blue-emitting FW-CDs with extremely high brightness and nanoscale uniformity were successfully fabricated. The FW-CDs, forming hydrogen bonds with cotton, exhibit a superior binding affinity, enhancing the whitening performance significantly with a whiteness index of 94.3, compared to 92.6 for VBL controls. Moreover, they endow the fabric with remarkable durability, ensuring 95.25% whiteness retention after 5 accelerated laundering cycles, and excellent UV stability, maintaining 97.61% of the initial whiteness after 96 h of UV exposure. The engineered textile system also exhibited remarkable multifunctionality: FW-CDs also have excellent antibacterial, antioxidant, and UV-shielding properties. At a concentration of 0.5% (o.w.f), the antibacterial rate against Escherichia coli and Staphylococcus aureus exceeds 99%. The DPPH radical scavenging rate is 58.6%, and the UV-protection factor (UPF) increases from 4.1 to 7.6. Moreover, the modification barely affects cotton’s original properties. This first demonstration of CDs integrating four functionalities (whitening/antibacterial/antioxidant/UV-blocking) with durability positions this technology as an industrially feasible nanomaterial solution within the textile industry.