Review of 2D Graphitic Carbon Nitride-Based Membranes: Principles, Syntheses, and Applications

Abstract

Membrane separation is a central area of research in chemical engineering because of its important status as the key technology in chemical separation and water treatment processes. Recently, polymeric graphitic carbon nitride (g-C3N4) has emerged as a candidate material for membrane applications because of its appealing physiochemical properties and ease of fabrication. Herein we review the progress of g-C3N4-based membranes, including the peculiarity of two-dimensional (2D) g-C3N4, the tailoring of functionality, and integration into membrane stacks for practical applications in gas separation, water purification, pervaporation, photocatalytic water filtration, oil-in-water separation, and polymer electrolyte membranes. Moreover, possible development directions of g-C3N4-based membranes are discussed along with the current challenges and future perspectives.

Molecular assembly of carbon nitride-based composite membranes for photocatalytic sterilization and wound healing

“…In comparison to conventional polymeric membranes, strong in-plane noncovalent bonds of the 2D-material-based membranes enhanced the mechanical strength and chemical stability, which are needed for the membrane to be utilized under harsh conditions. 75 As a result, the tensile test ( Fig. 3f and S27 † ) showed that the ultimate strength and Young's modulus of the pCN/CNTs membrane were better than those of the control pCN + CNTs and CNTs membranes, which were filtered using pCN and/or CNTs mixtures without PPA compounding.…”

Graphitic carbon nitride-based nanostructures as emergent catalysts for carbon monoxide (CO) oxidation

“…2.5.2.1 Hard templates. Hard templates like porous anodic metal oxide (i.e., alumina oxide (AAO) and ZnO) 82,112,113 and silica (i.e., SBA-15, SBA-16, FDU-12, and KIT-6) [114][115][116] are exhaustively used for the preparation of porous g-C 3 N 4 with different structures (i.e., nanotubes, nanorods, and nanospheres). This followed pioneering work done by Goettmann et al 117 who mixed cyanamide with 12 nm SiO 2 particles in water, which was heated to 550 °C for 2h and then 4 h, followed by immersion in NH 4 HF 2 for two days to remove the silica template.…”

“…24,77–80 There are various reviews discussing in detail the preparation methods of g-C 3 N 4 . 21,28,81–83…”

“…Hard templates like porous anodic metal oxide ( i.e. , alumina oxide (AAO) and ZnO) 82,112,113 and silica ( i.e. , SBA-15, SBA-16, FDU-12, and KIT-6) 114–116 are exhaustively used for the preparation of porous g-C 3 N 4 with different structures ( i.e.…”

Synthesis and up-to-date applications of 2D microporous g-C3N4 nanomaterials for sustainable development

“…For these reasons, g-C 3 N 4 membranes are used as active agents or emulsifiers on colloidal surfaces, and their ability to maintain high surface activity also in liquid-liquids, liquid-gases and liquid-solids has led to their application in cleaning, anti-fouling, gas purification, biological separation and wastewater treatment. 48 The g-C 3 N 4 with structural defects may allow the production of amine groups (primary and/or secondary) on the terminating edge of its monolayer, presenting basicity, which leads to the formation of g-C 3 N 4 multifunctionality. Thus, the surfaces of g-C 3 N 4 materials are endowed with fundamental nucleophilic properties that promote their valuable applications.…”