Solar thermal textiles for on-body radiative energy collection inspired by polar animals

Abstract Humans use textiles for maintaining thermal homeostasis amidst environmental extremes but known textiles have limited thermal windows. There is evidence that polar-dwelling animals have evolved a different mechanism of thermoregulation by controlling radiative energy exchange with the environment using a combination of light-absorbing and heat-retaining materials. Here we design a textile to mimic these adaptations to optimize direct radiative collection on the body. Two ultralightweight fabrics with complementary optical functions, a nylon “absorber” coated with a strongly-colored conjugated polymer and a nonwoven polypropylene “transparent insulator,” perform the same putative function as polar bear skin and hair, respectively. While retaining familiar textile qualities, these layers suppress radiative dissipation of body heat and maximize radiative absorption of visible light. Exposed to a radiance of 650 W/m2, representative of wintertime sunlight at high latitudes, the textile supports thermal homeostasis as low as -28oC. With increasing pressures to adapt to a rapidly changing climate, our work leverages conjugated polymers to evolve one of the oldest and most basic commodities —textiles.