Sustainable infrared-driven deposition of palladium nanoparticles on viscose for multi-functional textile engineering

Prolonged exposure to ultraviolet (UV) irradiation and microbial contamination correlated to the environmental pollution and ozone layer depletion caused serious health concerns. Nanotechnology offers promising solutions in functional textiles, particularly through nanoparticles with high surface energy, ionization capacity, and surface area. Herein, for the first time the exploitation of infra-red irradiation for controllable nucleation of PdNPs was investigated. This study is considered with the enhancement of UV protection and antimicrobial properties of viscose fabrics via infrared (IR)-assisted/in-situ self-clustering of palladium nanoparticles (PdNPs). PdNPs were synthesized within viscose matrix under varying conditions: two concentrations of PdCl₂ (100 and 200 mM), two pH levels (2.0 and 12.0), and before/after cationization using DADMAC. SEM and EDX analyses confirmed the deposition and elemental composition of nanoparticles. Particle size before cationization ranged from 7.8 ± 2.5 to 11.1 ± 2.5 nm, and 5.5 ± 1.7 to 2.4 ± 0.7 nm. Acidic media and DADMAC treatment is favored for smaller, spherical particles and better dispersion. After PdNPs modification, viscose showed very good - excellent UV-protection (UPF = 35.2-88.0). Excellent antimicrobial activity (microbial reduction = 90.5-94.3%) was obtained for modified viscose against different microbial pathogens. Multi-functional of viscose was prepared with good durability. The data demonstrate that, IR-assisted PdNPs functionalization is an effective and sustainable method for durable multi-performance viscose textiles.