Facile Fabrication of Slippery Lubricant-Infused CuO-Coated Surfaces with Different Morphologies for Efficient Water Collection and Excellent Slippery Stability.

Abstract

How to prepare multifunctional surfaces with high nucleation density and fast droplet removal during droplet condensation remains a challenge. It is believed that a water droplet on a superhydrophobic surface (SHS) in the Cassie state is inclined to convert to the Wenzel state under high-pressure or high-humidity conditions, which results in the pinning effect. Hence, it is necessary to form thermodynamically stable lubricant-infused surfaces (LISs) to be applied in water condensation, especially under extreme working conditions. In this work, CuO LISs with two different morphologies (chrysanthemum-like and dandelion-like structures) in the slippery state were prepared and the effect of surface morphology on water harvesting behavior was investigated. The results indicated that dandelion-like CuO consisting of nanoneedles exhibited inferior water harvesting behavior compared to chrysanthemum-like CuO consisting of nanolamellas due to worse lubricating oil loss. Furthermore, the strong intermolecular forces between the perfluoropolyether (PFPE) lubricating oil and perfluorodecanethiol (PFDT)-modified coating resulted in a durable lubricating layer, which exhibited favorable anti-icing, anticorrosion, and liquid repellency even under strong acid and alkali conditions, high shear force rate up to 7000 rpm, and long-time ultraviolet light irradiation for 12 h. This work paves the path for efficient droplet nucleation and removal, which has potential in water harvesting in arid regions and water condensation for power generation.