Copper Sulfide Nanoparticle/Cellulose Composite Paper: Room-Temperature Green Fabrication for NIR Laser-Inducible Ablation of Pathogenic Microorganisms

This work reports a new type of near-infrared (NIR) laser-inducible antimicrobial composite paper based on copper sulfide nanoparticles (CuS NPs). For the first time, a smart and green method to prepare CuS NPs was developed by taking advantage of the copper–amine complex as the copper source and sodium sulfide as the sulfur source at room temperature, in which a biopolymer xylan was used as the growth template and stabilizing agent. The obtained xylan/CuS NPs composites (CuS@Xylan NPs) were spherical and stable with an average diameter of ∼10 nm. CuS@Xylan NPs were subsequently allowed to penetrate into cellulose nanofiber (CNF) networks to prepare the composite paper. This CuS@Xylan NPs/CNF composite paper showed strong NIR laser-inducible antimicrobial effect on Escherichia coli, Bacillus subtilis, Stapylococcus aureus, and Aspergillus niger. In addition, the tensile strength, tear strength, and burst strength of the composite paper were improved likely due to the strong hydrogen bonding between xylan and CNFs. This study provides a novel strategy to synthesize CuS NPs and generation of a new proof-of-concept type of composite paper for convenient ablation of pathogenic microorganisms, which has a potential to be applied to skin wound infection prevention for rapid wound healing.