Filters assembled with graphene oxide (GO) nanosheets featuring uniform nanochannels exhibit excellent performance for molecular separation and hold great potential for water purification. However, the long and curved nanochannels constructed by highly ordered packing of conventional GO nanosheets seriously reduce the water permeability. Herein, a filter with heterogeneous nanochannels was prepared using Janus-like graphene oxide (JGO) via vacuum-assisted filtration and achieved high permeability without sacrificing the rejection rate. The JGO sheet possesses a special chemical structure with oxidized areas along the faces of the sheet, resulting in different interface properties for both sides of the JGO sheet. Therefore, the JGO filter fabricated by the vacuum-assisted self-assembly possesses both larger pores and smaller channels compared to common GO filters, providing higher permeability and rejection rates. The removal efficiency of the JGO-based filter towards various dye molecules exceeds 99%, and the permeability is maintained between 110 and 140 L m⁻² h⁻¹ bar⁻¹, which is more than three times that of the GO filter. This study demonstrates that the filters fabricated with Janus-like nanosheets exhibit both high separation efficiency and high permeability, showing promising application for water treatment.

中文翻译：

---

由类 Janus 氧化石墨烯纳米片制成的过滤器，具有异质纳米通道，可高效去除染料


由氧化石墨烯（GO）纳米片组装而成的过滤器具有均匀的纳米通道，表现出优异的分子分离性能，并在水净化方面具有巨大的潜力。然而，传统GO纳米片高度有序堆积所构建的长而弯曲的纳米通道严重降低了水的渗透性。在此，使用类Janus氧化石墨烯（JGO）通过真空辅助过滤制备了具有异质纳米通道的过滤器，并在不牺牲截留率的情况下实现了高渗透性。 JGO 片材具有特殊的化学结构，片材的表面有氧化区域，导致 JGO 片材的两面具有不同的界面特性。因此，与普通GO过滤器相比，真空辅助自组装制造的JGO过滤器具有更大的孔径和更小的通道，提供更高的渗透率和截留率。基于JGO的过滤器对各种染料分子的去除效率超过99%，渗透率保持在110至140 L m ⁻² h ⁻¹ bar ⁻¹