Developing an effective and sustainable method for the separation of oil and brine mixture is highly necessary for the restoration of environmental pollution caused by the loss of organic solvents during the lithium extraction process from brine. Herein, we report a facile and cost-efficient method to fabricate an underbrine superoleophobic mesh by one-step hydrothermal method. The synthesized CrO_x(OH)_3–2x/nickel mesh possesses flower-like nanostructure, exhibiting superior superhydrophilicity/underbrine superoleophobicity for different ratios of tributyl phosphate and sulfonated kerosene mixtures. Simultaneously, the CrO_x(OH)_3–2x /nickel mesh manifests high efficiency for oil and brine separation with an ultrahigh permeation flux (78136 L∙m⁻²∙h⁻¹) and excellent oil rejection efficiency (>99.17%). Furthermore, the as-prepared mesh exhibits high chemical stability, outstanding salt tolerance, and excellent mechanical properties. Importantly, the surface wettability can be changed from superhydrophilicity to superoleophobicity for several times only by ignition of the CrO_x(OH)_3–2x/NM on an alcohol burner for 10 s or modified by OTS. Altogether, the CrO_x(OH)_3–2x/nickel mesh has tremendous potential in practical oil-brine applications.

开发一种有效且可持续的油和盐水混合物分离方法对于恢复从盐水中提取锂过程中有机溶剂损失造成的环境污染是非常必要的。在此，我们报告了一种通过一步水热法制造海底超疏油网格的简便且具有成本效益的方法。合成的CrO _x (OH) _3-2x /镍网具有花状纳米结构，对不同比例的磷酸三丁酯和磺化煤油混合物表现出优异的超亲水性/超疏油性。同时，CrO _x (OH) _3–2x/镍网具有超高渗透通量（78136 L∙m ^-2 ∙h ^-1）和出色的排油效率（> 99.17％），表现出高效率的油和盐水分离。此外，所制备的网具有高化学稳定性、出色的耐盐性和优异的机械性能。重要的是，仅通过在酒精燃烧器上点燃 CrO _x (OH) _3-2x /NM 10 s 或通过 OTS 改性，表面润湿性可以从超亲水性变为超疏油性数次。总之，CrO _x (OH) _3-2x /镍网在实际油盐水应用中具有巨大的潜力。