10 - Graphene and its derivatives for environmental applications

Abstract

Graphene has provided an impetus towards revolutionary improvements in the performance and capabilities of technologies in various fields. Graphene oxide (GO), a graphene derivative, has been extensively studied for its abundant chemical functionalities, mechanical stiffness, biocompatibility, and layered structure with large specific surface area. Many oxygen-functional groups on GO offer reactive sites, enabling simple modifications for improving the performance of GO-based nanomaterials and further enabling the formation of robust and high-performance membranes, adsorbents, sponges, and composites. This chapter presents detailed literature on synthesis and modification of GO and its promising applications in membrane separations and adsorption. Overall, hydrophilic GO and functionalized graphene oxide (fGO) blended, polymer-mixed matrix membranes show improved permeability and antifouling properties, demonstrating potential for high throughput ultrafiltration membrane. Surface modification of membranes with GO demonstrate good permeability and selectivity for salt and dyes separation. A modified GO laminate membrane showed enhanced stability in creating 2D nanofluidic channels that improve membrane permeability and rejection. Further, simple modified GO studies show its potential for water purification using adsorption techniques. The covalent functionalization of GO with amines and ionic liquids showed excellent adsorption properties for removing dyes and heavy metals from aqueous solution. Thus, GO showed excellent potential as a high-performance material for a new generation of water treatment technologies. This chapter explores graphene-based nanomaterials and their performance in environmental remediation as well as the parameters that influence their capacity.