Hammerhead Shark‐Inspired Microvillus‐Structured Ionic Elastomers for Wet Gas Sensing Based on Solvated Ion Transport

Abstract Water molecules are ubiquitous disruptors of conventional gas sensing materials, often leading to diminished sensing performance in materials that are reliant on electronic signal transmission. This creates the pressing need for efficient gas sensing materials with anti‐humidity interference properties. Here, a hammerhead shark‐inspired microvillus‐structured ionic elastomer based on ionic signal transmission in nanoconfined space is constructed by incorporating ionic liquids into a polymer matrix. The ionic elastomers with optimized microvillus structure demonstrated a 1.68‐fold higher response than that of the flat ones, short response time (9 s) toward 30 ppm triethylamine (TEA), excellent selectivity and low limit of detection (LOD) (104.56 ppb). Such sensing performance serves as a proof‐of‐concept for effectively combining solvated ion transport in nanoconfined space with microvillus structure design to develop advanced sensing systems. With such sensing materials, an evident response (23.52%), a similar response time (12 s), low LOD (498.05 ppb), and long‐term stability (at least 30 days) are achieved at the relative humidity of 70%. Mechanistic investigations revealed that effective transport of solvated ions is facilitated after sequential water and TEA surroundings while the microvillus structure significantly enhanced gas transport. Furthermore, the utility of such a sensing system is demonstrated in shrimp decay monitoring under wet conditions.