Stable slippery liquid-infused anti-wetting surface at high temperatures†
Abstract
Recently developed slippery liquid-infused surfaces (LIS) offer a new approach to construct anti-wetting surfaces due to their excellent repellence of various liquids. However, previous studies about LIS are mainly performed at room temperature or low temperature and the LIS with stable anti-wetting at high temperatures are rare. Here we report a facile method to prepare LIS with high-temperature resistance. We directly employed chemically etched stainless steel (CESS) as the substrate structure, which can be applicable to objects regardless of their shapes and sizes. By choosing silicone oil to infuse the silanized CESS, a slippery surface with a very low sliding angle (ca. 2°) was formed, and the successful preparation can be achieved even when the silanized CESS was annealed at a temperature of 600 °C. The as-prepared LIS showed excellent anti-wetting for both room-temperature water and hot water at high temperatures. On the basis of stable LIS with high-temperature resistance, we investigated the influence of temperature on the droplet movement on LIS, and found that there were three movement states for both the sliding and impacting of water droplets on LIS with increasing temperature. We envision that our proposed approach can broaden the applications of LIS in engines, medical instruments, and daily life.