Hierarchically designed 3-D printed porous nylon fabric-based personal thermoregulatory for radiative and directional wick-evaporative cooling

Energy consumption is increasing with global warming which remains a great challenge towards sustainable growth. Radiative cooling is an emergent technology towards personalized thermoregulation that radiates heat to outer space to attain self-cooling providing thermal comfort to humans while outdoors through economical way without any energy consumption. Herein a hydrophobic-hydrophilic porous nylon fabric (PNF) composite having unique pores across the composite with hierarchical silver nanoparticles decorated zinc stannate nanorods (Ag@ZTO) synthesized directly over the PNF. We designed the composite by novel and quick threedimensional (3D) printing technique for the first time that utilizes synergistic innovative integration of radiative and wick-evaporation cooling. The high reflectance of solar irradiance (89.5%) and high emissivity of human body thermal radiation (91.8%) permitted the textile to reduce the temperature of simulated skin by 19.3 degrees C under direct sunlight demonstrating its superior passive cooling capability. An excellent water vapor transmission rate, water-wicking, washability, durability, tensile strength (70.8% compared to bare PNF) is demonstrated for the composite and a high one-way transport index R (1368 %) shows its unidirectional liquid transport behavior. This approach of designing fabric through tailoring the properties by cost-effective techniques offers new routes for personal thermoregulatory and moisture management towards advanced functional textiles introducing a pioneering direction to sustainable energy.