(385af) Plasma-Treated Nanoporous Graphene Oxide Membranes for Molecular Separation

Graphene oxide (GO) is an attractive material for molecular separation due to its abundant π-electron system, which facilitates microwave absorption and enables efficient structural modifications. In this study, nanoporous GO with a high density of sp² carbon domains was synthesized via a 60-second microwave-assisted annealing process. These GO flakes were intercalated with MXene sheets and subsequently exposed to plasma treatment to induce rapid self-crosslinking between GO and MXene components. While previous studies have demonstrated the self-crosslinking behavior of GO–MXene membranes, this work highlights the enhanced crosslinking efficiency achieved through plasma activation.

The resulting membranes exhibit smooth sp² carbon surfaces and a dense network of nanopores, leading to significantly improved structural stability and molecular sieving performance. Under low-pressure operation, the membranes showed high water permeance (3.6 LMH/bar) and sustained long-term performance. Salt rejection tests across a range of concentrations (500–1000 ppm) revealed high rejection efficiencies, exceeding 90% for both NaCl and MgCl₂. Moreover, the membranes achieved complete rejection (100%) of various dye molecules, demonstrating their potential for versatile separation applications. This study underscores the synergistic effects of nanopore generation, MXene intercalation, and plasma-assisted crosslinking in advancing next-generation 2D nanocomposite membranes for water purification and molecular separations.