A Superslippery Biomimetic Leaf with Self-Driven Water Absorption Performance for Robust Spectral Simulation

Biomimetic leaf materials show great potential for applications such as spectral simulation, self-cleaning surfaces, and moisture management. However, they face a daunting challenge: the incompatibility between antifouling, self-cleaning properties and hygroscopic water absorption capability. To address these challenges, we design a biomimetic leaf based on antifouling superslippery fabric composites (liquid-infused polydimethylsiloxane elastomer laminated with hydrogel in spacer fabrics, IPHSF), which exhibits self-driven water absorption performance for robust spectral simulation. The composites feature a liquid (silicone oil)-infused, superslippery polydimethylsiloxane elastomer upper layer that mimics the leaf epidermis. Moreover, the hydrogel, enriched with calcium ions, simulates the water storage and transpiration functions of leaf mesophyll. Furthermore, the spacer fabrics serve as the substrate and framework, providing space for hydrogel loading and mechanical support. IPHSF exhibits reflectance spectra closely resembling those of natural leaves across a broad spectral range (400–2500 nm), consistently demonstrating a spectral correlation coefficient greater than 0.96, a cosine similarity exceeding 0.97, and an ultralow average Euclidean distance of 0.628. Notably, the upper layer endows the material with remarkable antifouling capability, as evidenced by a small sliding angle of 2.5° and the recovery of the superslippery layer through a self-secretion mechanism, which restores sliding velocity within 180 min. Moreover, IPHSF maintains excellent spectral stability, with the variation in the “water absorption valleys” limited to 2% at 1450 and 1930 nm after simulated rainfall, whereas control samples without the antifouling layer exhibit much larger shifts exceeding 20% at 1450 nm and 6% at 1930 nm. Therefore, our strategy prevents the loss of hygroscopic agents and enables an antifouling self-recovery mechanism. By overcoming poor antifouling properties and suppressing ion leakage under harsh environments, the designed biomimetic leaf maintains stable spectral performance. The resultant IPHSF with outstanding antifouling and self-driven water absorption performance holds great potential for biomimetic spectral simulation in harsh environments. This work advances the development of next-generation biomimetic fabric materials for diverse applications.