Periodic stepped micropapillae superhydrophobic surface with ultralow ice adhesion for efficient anti-icing/deicing

Icing and ice accumulation pose a huge hazard to human daily life and industrial applications, creating a huge demand for anti-icing/deicing surfaces. Superhydrophobic surfaces are potentially icephobic, but they are prone to be self-locked when exposed in the frozing condition of cold and humid environments, which limits their practical application. Here, inspired by the surface of arrow bamboo leaf, a periodic stepped micropapillae superhydrophobic surface (PSPs) with ultralow ice adhesion is prepared via femtosecond laser processing and hydrothermal method. Due to the micro/nano multiscale and stepped structure, the PSPs forms large and stable air cushions that shows excellent anti-icing/deicing capabilities. Under the action of Laplace pressure and stepped structure, microdroplets on the surface tend to form eccentric bouncing, which enhances the self-removal ability of microdroplets. The delayed icing time of PSPs reaches 48 min, 7.4 times that of the bare surface. The ice adhesion of PSPs is reduced to 1.25 kPa, only one-third of the no-stepped micropapillae surface. In addition, PSPs exhibits high delayed icing capacity in the supercooled water impact experiments under high-humidity environments (about 85%RH). This work provides new insights for designing superhydrophobic surfaces with anti-icing and deicing ability, which can further promote the development of anti-icing/deicing for such surfaces.