In this paper, we report for the first time the fabrication of cauliflower-like Ni(OH)₂ particles–coated fabrics with inverse special wettability via a facile hydrothermal method. The coated fabric is superhydrophilic in air and superoleophobic underwater, which can be changed into superhydrophobicity after being modified by long-chain fatty acid. After the superhydrophilic fabric is wetted by water in advance, hot alkaline water can be removed from the light oil/water mixture driven by gravity. Also, heavy oil can be removed from the heavy oil/hot alkaline water mixture under the action of gravity using superhydrophobic fabric. The separation efficiencies of the two fabrics for different mixtures of hot alkaline water and light or heavy oil are more than 95.8%. Furthermore, a two-way separation device was designed via integrating a pair of fabrics with opposite wettability. The device can continuously separate oil and water at the same time from oil/hot alkaline water mixture via one-step route with high separation efficiency without consideration of the density of the oil. Moreover, the superhydrophilic fabric is capable of separating various oil-in-water emulsions. We believe that the as-prepared fabrics and the designed device may find wide application in separating oil from alkaline water.

在本文中，我们首次报道了花椰菜状Ni（OH）₂的制备通过简便的水热法，颗粒涂覆的织物具有特殊的反润湿性。涂层织物在空气中是超亲水的，而在水下是超疏油的，经长链脂肪酸改性后可转变为超疏水性。预先将超亲水性织物用水润湿后，可以在重力作用下从轻质油/水混合物中除去热的碱性水。同样，可以使用超疏水性织物在重力作用下从重油/热碱水混合物中除去重油。两种织物对热碱性水和轻质或重质油的不同混合物的分离效率均超过95.8％。此外，通过整合一对具有相反润湿性的织物，设计了一种双向分离装置。该装置可通过一步法从油/热碱水混合物中连续不断地同时分离出油和水，分离效率高，而无需考虑油的密度。而且，超亲水性织物能够分离各种水包油乳液。我们相信，所制备的织物和设计的装置可以广泛地用于从碱性水中分离油。