Preparation And Application Of Photothermal Silk Fabric With Deposited Copper Sulfide Nanoparticles

Silk fabric(SF)has the characteristics of soft hand,good breathability,moisture absorption,which makes it provide an ideal environment for bacteria growth.Copper sulfide nanoparticles(CuSNPs)belong to a transition metal sulfide with excellent light-thermal conversion property.According to the application characteristics,a multifunctional silk fabric with rapid photothermal antibacterial ability was constructed via deposition of CuSNPs onto silk fabric.In this paper,the effects of different soft templates on the styles of CuSNPs and stability of the obtained solution were explored,via the combined use of copper ammonium and thiourea.Subsequently,in-situ growth of CuSNPs on silk fabrics was also carried out.Based on the above-mentioned work,an organic-inorganic doped functional silk fabric(SF/PANI/CuS)was also constructed with the guidance of polyaniline(PANI),and the photothermal antibacterial ability and oxidation resistance for the composite fabric were also explored.More details on the contents and results are listed as follows.The effect of different polar groups(carboxyl,hydroxyl,ammonium,etc)on the stability of nano-copper sulfide solution was firstly explored through different soft templates.The particle size,morphology,crystal structure and photothermal properties of the nanoparticles were also evaluated.The results reveal that the nano-copper sulfide solution prepared with chitosan quaternary ammonium salt(QCS)as a soft template has higher dispersion stability,the obtained CuSNPs exhibit high specific surface area and has encouraging photothermal effect.In addition,antibacterial silk fabric was prepared through a two-step method,where a chitosan quaternary ammonium salt(QCS)was used as a template to temporarily negative sulfur ions,which were further transferred to silk fibers containing copper ammonia ions.The morphology,structure,and corresponding antibacterial ability for the obtained CuSNP-deposited silk fabric were examined.The obtained results reveal that the prepared materials,formed by interactions between silk fiber and QCS chains,exhibit uniform size and typical structural characteristics of CuSNPs.Moreover,a rapid antibacterial efficiency of the composite silk fabric was determined under light irradiation(400 m W/cm~2),resulting in 99.99%bacteria death of Staphylococcus aureus(S.aureus)and Escherichia coli(E.coli)within 5 min of irradiation.Additionally,the fabric of SF/QCS/CuS exhibits excellent antiultraviolet properties,with a UPF value of 165.Furthermore,more complexing sites on fiber surfaces were provided via the polymerization of PANI onto silk fibers,aiming at constructing an organic-inorganic doped multifunctional textiles(SF/PANI/CuS)with enhanced photothermal properties.In additional,the self-cleaning ability and antioxidant properties of the functional textile were also explored by encapsulation of polydimethylsiloxane(PDMS).The results reveal that the composite textile of SF/PANI/CuS achieved satisfactory UV resistance.The inactivation toward S.aureus and E.coli reached 99.9%when irradiated for 5 min with the light intensity of 200 m W/cm~2,remaining the similar level even after washing 10 times.Additionally,PDMS encapsulation protects the deposited CuSNPs from air oxidation without sacrificing its photothermal performance.The exhibited results provide a new idea for the eco-friendly development of functional silk-based products.