Abstract Desert sand as an abundant natural resource rarely has been reconsidered and reutilized due to its superhydrophilicity. Aiming at the combination of super-wettability with sand resource, we successfully design the aligned Cu(OH) 2 nano-needles on the sand grain surfaces through a skillful strategy and conferred superhydrophobic properties on them in this study. The water contact angle and rolling angle are shown to be ~ 158° and ~ 6°, which break our traditional understanding towards desert sand, i . e ., superhydrophilicity. More importantly, the selective superhydrophobic-superoleophilic wettability and the cavities between nano-needles and sand grains allow the sand to be a good candidate for efficient oily water treatment. The as-prepared superhydrophibic sand can not only absorb light oils from water surface, but separate heavy oils from oil/water mixtures. The speed of oil/water separation is up to 16,985 L m − 2 h − 1 when a 0.35 cm thickness of superhydrophobic sand layer is used. Significantly, it exhibits both high separation rate and high separation efficiency (> 99.5%). The as-prepared superhydrophobic sands are expected to become a new candidate of highly efficient oil/water separation material and to realize the reutilization of desert sand resource.

中文翻译：

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具有排列的Cu(OH) 2 纳米针结构的超疏水砂粒可有效处理含油水

摘要 沙漠沙作为一种丰富的自然资源，由于其超亲水性而很少被重新考虑和再利用。针对超润湿性与砂资源的结合，我们通过巧妙的策略成功地在砂粒表面设计了对齐的Cu(OH) 2 纳米针，并在本研究中赋予其超疏水特性。水接触角和滚动角显示为~158°和~6°，这打破了我们对沙漠沙子的传统理解。例如，超亲水性。更重要的是，选择性超疏水-超亲油润湿性以及纳米针和砂粒之间的空腔使砂成为有效处理含油水的良好候选者。所制备的超疏水砂不仅能吸收水面的轻油，但从油/水混合物中分离重油。当使用 0.35 cm 厚的超疏水砂层时，油/水分离速度高达 16,985 L m - 2 h - 1。值得注意的是，它表现出高分离率和高分离效率（> 99.5%）。制备的超疏水砂有望成为高效油水分离材料的新候选，实现沙漠砂资源的再利用。