Simultaneous dyeing and deposition of silver nanoparticles on cotton fabric through in situ green synthesis with black rice extract

A novel green route was explored for production of multifunctional cotton fabric involving simultaneous dyeing and deposition of silver nanoparticles (Ag NPs) on cellulose fiber. In the preparation process, Ag NPs were simultaneously synthesized and deposited on the fabric through in situ synthesis using silver nitrate and black rice aqueous extract without other chemicals. In this work, black rice extract of anthocyanin was introduced as a natural source for reducing agent and dye. UV–Vis spectra and SEM confirmed that Ag NPs were successfully produced and evenly distributed on the surface of the cellulose fiber. Moreover, results indicated that the pH value of the synthesis bath greatly influenced the apparent color and color strength of the treated samples. When the pH value of the synthesis bath was 10, better K/S value, washing fastness, and UV protective properties were exhibited compared with other pH values. In addition, the treated cotton fabric showed outstanding antibacterial property against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). The antibacterial rate of treated samples was still more than 80% for E. coli and S. aureus after 25 home laundering cycles. This study provides an eco-friendly method to prepare an antibacterial cotton fabric with good resistance to washing.