Durable One-Dimensional Liquid-Infused Surface for Practical Dropwise Condensation Enhancement

Suitable contact angle (CA) and contact angle hysteresis (CAH) of liquid-infused surfaces (LISs) make them promising candidates for condensation enhancement. However, their practical application encounters restrictions arising from issues such as low durability, unscalability, and high cost. In this study, aluminum covered with silicone oils of various viscosities and decamethylcyclopentasiloxane (D5) is exposed to ultraviolet (UV) light for two different periods to produce a durable, yet low-cost, 1-D LIS without the use of hazardous materials. For short-term exposure, 10 h of radiation is utilized, whereas long-term exposure depends on the gelation time of the lubricants. Tests reveal that all lubricants are chemically attached to the substrate, possessing a CA of >100° and CAH of lower than 10°. Furthermore, the fabricated samples can reduce the corrosion current density by up to 2 orders of magnitude with respect to bare aluminum. The condensation test reveals that the surface, covered with 5 cSt silicone oil that is exposed to UV light for 10 h, enhances the condensed water by 29%, 38%, and 39% at subcooling temperatures of 14.5, 10, and 5.5 K compared to bare aluminum, respectively. Additionally, compared with the literature, the durability of the fabricated LIS is improved by 350%.