Laser Ablation‐Induced Boron Nitride Aerogels with Intrinsic Photoluminescence for Efficient Information Encryption

Abstract Boron nitride (BN) aerogels, dual interconnecting network of BN nanoscale building blocks, and plenty of air within these nanoscale building blocks, have great potential in many emerging fields. However, fast synthesis and emerging applications, e.g., information encryption, are still challenging for advancing BN aerogels. Herein, intrinsic photoluminescent BN aerogels with programmable patterns are developed via laser ablating of melamine diborate (M2B) aerogel. The obtained BN aerogel exhibited typical hollow‐microsphere structures and blue fluorescence phenomenon, which are totally different from BN aerogels reported elsewhere. This BN aerogel exhibited excellent thermal insulation properties (0.027 W mK −1 ), transient fluorescence feature (3 ns average radiative lifetime), high quantum yield (18.45%), and excellent weather ability (e.g., resistance to high temperature, solar irradiation, and humidness). By programming the laser moving path, different fluorescent patterns (e.g., various security labels, secret matching keys, quick response codes) of BN aerogels can be processed, which promises excellent information encryption in the field of Internet of Things, etc. The results may inspire researchers to fabricate more aerogels with this fast laser‐ablation strategy and the resulting intrinsic fluorescent BN aerogels may find significant applications in some emerging fields.