Seasonal Adaptive Slippery Surface: Temperature-Mediated Reversible Switching and Sustained Slipperiness via Composite Solid Oil Reservoir Design.

Slippery Liquid-Infused Porous Surfaces (SLIPS) have received much attention in anti-icing, anti-fouling, etc. However, the strong interaction between droplets and lubricants causes lubricant loss, limiting their practical applications. Here, inspired by the structure and function of hippopotamus skin, we constructed a novel SLIPS (CPSC) capable of retaining low-viscosity silicone oil on the surface. CPSC was fabricated by creating inorganic particle oil storage units composed of rigid microshells and nanoparticles, which were subsequently filled with silicone oil and crosslinked within a silicone polyurethane matrix. CPSC surfaces exhibit excellent lubricating properties, with water droplets readily sliding off at angles as low as 4.6°, and maintain stable durability even after 1000 wiping cycles. This "solid-like" surface lubrication mode gives CPSC low ice shear strength (22 kPa) and de-icing cycle durability, and shows many advantages over conventional SLIPS in extreme environments such as centrifugal and water impact; while CPSC surface can be switched to an enhanced liquid lubrication mode when the ambient temperature rises, in order to cope with the vigorous biological activities and fouling adhesion on the surface in summer, avoiding the problem of idle functionality of traditional anti-icing coatings during non-icing periods, and bringing new hope for the sustainable use of SLIPS.