Enhancing the Dye-Rejection Efficiencies and Stability of Graphene Oxide-Based Nanofiltration Membranes via Divalent Cation Intercalation and Mild Reduction

Abstract

Laminar graphene oxide (GO) membranes have demonstrated great potential as next-generation water-treatment membranes because of their outstanding performance and physicochemical properties. However, solute rejection and stability deterioration in aqueous solutions, which are caused by enlarged nanochannels due to hydration and swelling, are regarded as serious issues in the use of GO membranes. In this study, we attempt to use the crosslinking of divalent cations to improve resistance against swelling in partially reduced GO membranes. The partially reduced GO membranes intercalated by divalent cations (i.e., Mg2+) exhibited improved dye-rejection efficiencies of up to 98.40%, 98.88%, and 86.41% for methyl orange, methylene blue, and rhodamine B, respectively. In addition, it was confirmed that divalent cation crosslinking and partial reduction could strengthen mechanical stability during testing under harsh aqueous conditions (i.e., strong sonication).

Layered double hydroxide/boron nitride nanocomposite membranes for efficient separation and photodegradation of water-soluble dyes

“…18 GO membranes have been demonstrated to have dye rejection values of 98.4%, 98.9% and 86.4% for MO, MB and RhB respectively. 40 This journal is © The Royal Society of Chemistry 2023 90% for EB. 41 It is therefore evident that the LDH/BNOx membranes reported exhibit exceptional retention for larger dyes such as EB (dimensions: 1.2 nm × 3.1 nm), as well as smaller dyes such as MB (dimensions: 1.4 nm × 0.6 nm), and are in line with some of the best results reported in the literature.…”

Self-Cross-Linking of MXene-Intercalated Graphene Oxide Membranes with Antiswelling Properties for Dye and Salt Rejection

“…11,12 For instance, a study demonstrated that the cross-linking of divalent cations could improve resistance against swelling in partially reduced GO membranes, leading to improved dye-rejection efficiencies of up to 98.88% for certain dyes. 13 In another research by Chandio et al, 14 a GO membrane was fabricated by employing a cross-linker, which was chosen to be serine amino acid (SAA), and reducing agent. The fabricated membrane showed impressive results by appreciably rejecting dyes like rhodamine B and methyl blue and salts like NaCl, MgCl 2 , and Pb(NO 3 ) 2 while maintaining ultrafast permeability.…”

“…Recent developments have focused on enhancing the efficiency and stability of these membranes. , For instance, a study demonstrated that the cross-linking of divalent cations could improve resistance against swelling in partially reduced GO membranes, leading to improved dye-rejection efficiencies of up to 98.88% for certain dyes . In another research by Chandio et al, a GO membrane was fabricated by employing a cross-linker, which was chosen to be serine amino acid (SAA), and reducing agent.…”

High Flux Nanofiltration Membranes with Double-Walled Carbon Nanotube (DWCNT) as the Interlayer

“…With population growth and economic development, fresh water scarcity has become extremely serious [ 1 , 2 , 3 , 4 , 5 ], and 25% of the population currently do not have enough fresh water. Due to low energy requirements, good stability and environment compatibility, membrane separation technology has been widely applied to alleviate the shortage of water resources.…”