Loofah‐Inspired Ultralight and Superelastic Micro/Nanofibrous Aerogels for Highly Efficient Thermal Insulation

Abstract Extreme cold events are becoming more frequent and intense around the world, imposing a huge burden on human health and global economy. However, developing fibrous materials featuring ultralight weight, high shape retention, and high thermal insulation to withstand extreme conditions remains a great challenge. Herein, inspired by the natural porous loofah, an ultralight and superelastic micro/nanofibrous aerogel (MNFA) that integrates hierarchical pores and stable physical entanglements is directly synthesized via gelation electrospinning technology. By manipulating the solution/water molecules interaction of the charged jets, a hierarchical porous structure consisting of fibrous porous networks and aerogel microfibers is developed, which endows MNFA with high porosity (99.7%). Benefiting from the stable physical entanglement structure between the rigid microfibers and flexible nanofibers, the resulting MNFA can withstand large tensile stress (4000 times of its weight) and 1000 compression cycles without being damaged. Moreover, MNFA exhibits ultralight feature (3 mg cm⁻³) and high thermal insulation performance (low thermal conductivity of 25.3 mW m⁻¹ K⁻¹), making a promising contender for highly efficient thermal insulation. This work can offer fresh perspectives on the design and advancement of advanced fibrous aerogels for a variety of uses.