Microplastic particles (MPs) have been identified as a potentially emerging threat to water environment and human health. It is thus an urgent challenge to develop facile and efficient methods for removing MPs from surface water and even ground water. Herein, we report a series of biomimetic gill-inspired membranes (BGIMs) with oblique and direct-through micropores for the efficient removal of MPs by the cross-flowing filtration of polluted water. These BGIMs were constructed via a bidirectional freezing method of thermally induced phase separation. They show a tunable oblique pore angle of 85° to 25° and an average pore size of 3.5 μm to 10.5 μm. MPs smaller than the pore size can be rejected via a ricocheted away mechanism. BGIMs with an oblique pore angle of 25° and an average pore size of 10.5 μm can remove 97.6% of MPs (700 nm in diameter) from water by cross-flowing on the membrane surface with a rate of 0.43 or 0.51 m/s. This effectual removal efficiency highlights BGIMs as a promising approach for quickly remediating water from the pollution of MPs.

微塑料颗粒 (MPs) 已被确定为对水环境和人类健康的潜在新兴威胁。因此，开发简便有效的方法从地表水甚至地下水中去除 MPs 是一项紧迫的挑战。在此，我们报告了一系列具有倾斜和直通微孔的仿生鳃膜 (BGIM)，用于通过污染水的错流过滤有效去除 MP。这些 BGIM 是通过热致相分离的双向冷冻方法构建的。它们显示出 85° 至 25° 的可调斜孔角和 3.5 μm 至 10.5 μm 的平均孔径。小于孔径的 MP 可以通过弹跳机制被拒绝。斜孔角为 25°、平均孔径为 10.5 μm 的 BGIM 可以去除 97。通过以 0.43 或 0.51 m/s 的速率在膜表面交叉流动，6% 的 MP（直径 700 nm）来自水中。这种有效的去除效率突出了 BGIM 作为一种有前途的方法，可以快速修复 MPs 污染中的水。