(29j) Enhanced Permeance and Selectivity of Plasma-Treated Mxene-Intercalated Nanoporous Graphene Oxide Membranes

Graphene oxide demonstrates exceptional microwave absorption capabilities attributed to the abundance of π electrons within its molecular structure, rendering it an optimal candidate for implementing the intercalation strategy. In this study, nanoporous graphene featuring a substantial density of sp2 carbon domains was fabricated via a 60-second microwave-assisted annealing process. These nanoporous graphene oxide flakes were intercalated using MXene flakes, followed by plasma treatment to facilitate self-crosslinking between the nanoporous graphene oxide and MXene constituents. While our prior research has showcased the self-crosslinking of GO-MXene membranes, the efficacy of crosslinking in this study is notably enhanced through plasma treatment, enabling rapid crosslinking. The resultant membrane, characterized by smooth sp2 carbon domain surfaces and densely populated nanopores due to effective crosslinking, exhibited high permeance and long-term stability under low-pressure conditions when subjected to microwave-plasma treatment. Furthermore, the performance of these membranes was evaluated under varying salt concentrations (500-1000 ppm), demonstrating significant rejection rates (>90%) for MgCl2 and NaCl. Additionally, these membranes exhibited high dye rejection rates (>90%) for various dye molecules.