Bioinspired Porous Hydrogel Templating Enables the Ambient Synthesis of Highly Adhesive Aerogels for Long‐Term Wildfire Prevention and Infrastructure Protection

Abstract Wildfires present a growing risk to ecosystems, human safety, and infrastructure, particularly at vulnerable wildland–urban interfaces (WUIs). Existing fire suppressants and retardants are essentially limited by poor adhesion, water dependency, and susceptibility to weathering, rendering them ineffective for long‐term prophylactic protection. Inspired by the robust, humidity‐resistant adhesion mechanism of snail mucus, a sprayable porous dual‐network hydrogel platform is developed. In its hydrated state, the softened foaming gel conformally adapts to the target substrate by low‐energy deformation. After ambient drying, this gel adheres to vegetation and transforms into a highly adhesive, mechanically robust aerogel without collapse. The resulting aerogel has exceptional properties: strong substrate adhesion (shear strength >2.0 MPa on wood), outstanding thermal insulation (<27 mW·m ⁻¹ ·K ⁻¹ ), high flame retardancy (limiting oxygen index (LOI)>40%), and remarkable water resistance. It is demonstrated that this aerogel forms an in situ thermal barrier and protective char/silica layer after flame exposure through spontaneous contraction of surface pores, significantly reducing the ignition probability. Wildfire suppression tests confirm its superior efficacy as a long‐lasting firebreak on vegetation, retaining functionality after several days of weathering and water exposure. This porous hydrogel platform and its derived aerogel provide a promising solution for persistent wildfire mitigation and durable protection of WUI infrastructure.