توصيفگر ها :
نانوساختار , مگنتايت , لايه نشاني پارچه , پارچه رسانا , نانولولههاي چند ديواره , پارچه مغناطيسي
چكيده انگليسي :
Magnetite (Fe3O4) nanoparticles are utilized in applications such as sensors, hyperthermia and data storage due to their properties, including superparamagnetism, biocompatibility, wave absorption, and ease of synthesis. Another versatile nanostructure is multi-walled carbon nanotubes (MWCNTs). These materials, with their exceptional properties like high conductivity, flame retardancy, and tensile strength, are suitable for applications such as medicine and sensors. In this study, carboxylated multi-walled carbon nanotubes (MWCNTCOOH) and magnetite nanoparticles were synthesized in-situ, forming a new nanostructure, which was then in-situ coated onto nylon knitted fabric. The presence of a textile substrate, particularly knitted fabric, added unique functionalities to the final fabric.To characterize and investigate the effect of different weight ratios of materials on the properties of the final fabric, the designed syntheses for coating the fabric were carried out with different weight ratios of iron salts to multi-walled carbon nanotubes (Fe3O4: MWCNT-COOH) at 1:1, 2:1, 4:1, 6:1, and 8:1, respectively. Surface structure, chemical analysis, microstructure, electrical conductivity, magnetic properties, flame retardancy, and antibacterial properties were studied. FESEM results and surface structure analysis showed that increasing the amount of iron salts affected the morphology: up to 2 ratio a layer, at 4 and 6 ratios, a combination of layers and particles was observed; and at an 8 ratio, a layered structure reappeared. Additionally, magnetite nanoparticles caused the welding of carbon nanotubes. These morphological changes were also observed in the magnetic properties of the fabric. As the coating amount increased and particle size became larger, the magnetic property showed an increasing trend up to a 6:1 ratio (from 0.06 to 1.00 emu/g) and then decreased at an 8:1 ratio (0.71 emu/g) due to higher particle aggregation in the solution. This trend was also observed in the XRD spectrum with changes in the crystal size of the magnetite nanoparticles. Overall, the increase in iron salts improved the adsorption of carbon nanotubes to the fabric and enhanced coating and conductivity. The formation of larger particles disrupted conductivity and exhibited a morphology-dependent behavior. The highest conductivity of 4.78 S/m was achieved at a synthesis ratio of 2. The optimal condition for achieving a suitable balance of both magnetic and conductive properties was found at a synthesis ratio of 6. The incorporation of these nanostructures into the fabric not only improved flame resistance and reduced burn length by approximately 50% but also imparted excellent photothermal properties. The optimized fabric sample heated up to 81°C from a distance of 10 cm from the light source within 106 seconds, and its photothermal properties were cyclically tested, showing good reversibility after five cycles. At a distance of 15 cm from the source, the fabric still reached temperatures of 65°C and then returned to lower temperatures. The multifunctional fabric also exhibited significant antibacterial properties, with up to 69.88% and 99.92% efficiency for E. coli under non-irradiated and irradiated conditions, respectively, and 64.7% and 99.7% for S. aureus. In conclusion, the fabric is a multi-functional fabric with conductive and magnetic properties, flame resistance, photothermal, and antibacterial features, suitable for applications in various sensor types and beyond
