Super‐White Boron Nitride Aerogel‐Enabled High‐Energy Laser Irradiation Protection

Abstract Aerogels are ultralight solid materials with three‐dimensional interconnected porous structures that offer considerable advantages for various protective applications. Lasers have led to various technological revolutions in aerospace, medical science, and industrial manufacturing. However, shielding against high‐energy laser irradiation using aerogels has rarely been reported. A super‐white (reflectivity >98%) boron nitride (BN) aerogel constructed using BN nanoribbons is developed in this study for high‐energy laser protection. Large numbers of BN nanoribbons serve as randomized and disordered optical nanobarriers for intense backlight scattering, which contribute to high broadband reflectivity. Combined with the low thermal conductivity of the aerogel structure and the excellent high‐temperature stability of BN, the resulting BN aerogel exhibits a high protective threshold of 2.1 × 10⁴ W cm⁻². Moreover, the BN aerogel possesses a soft porous network and a low thermal expansion coefficient, which is promising for tolerating the thermal stress and shock of local high‐temperature fields caused by laser irradiation. The successful laser shielding by the super‐white BN aerogel may be helpful for designing and fabricating advanced aerogel‐based lightweight anti‐laser materials.