Environmental applications of graphene-based nanomaterials

Abstract

Graphene-based materials are gaining heightened attention as novel materials for environmental applications. The unique physicochemical properties of graphene, notably its exceptionally high surface area, electron mobility, thermal conductivity, and mechanical strength, can lead to novel or improved technologies to address the pressing global environmental challenges. This critical review assesses the recent developments in the use of graphene-based materials as sorbent or photocatalytic materials for environmental decontamination, as building blocks for next generation water treatment and desalination membranes, and as electrode materials for contaminant monitoring or removal. The most promising areas of research are highlighted, with a discussion of the main challenges that we need to overcome in order to fully realize the exceptional properties of graphene in environmental applications.

Graphene membranes for water desalination

“…7b. 24 In addition to the size-exclusion mechanism, ions can be separated from water by stacked graphene membranes through electrostatic interactions with the GO sheets. In a related study, 64 the diffusion properties of various ions in different sodium salt solutions through a GO membrane were determined.…”

“…Layered oxygenated graphene sheets, that is, those including oxygen functional groups, such as epoxides, carboxyls, hydroxyls and alcohols, on their basal planes and edges, are called GO. 23,24 GO is made via oxidation of natural graphite flakes by using strong oxidants, such as KMnO 4 , KClO 3 or NaNO 2 , along with a strong acid, for example, concentrated sulfuric acid or nitric acid. Subsequently, single GO sheets can be exfoliated by ultrasonication.…”

Graphene/PVDF flat-sheet membrane for the treatment of RO brine from coal seam gas produced water by air gap membrane distillation

“…Graphene has attracted considerable attention in recent years for water treatment and purification processes as it improves the membrane properties and adds functionalities such as anti-fouling properties [21,22]. The possibility of cheaper synthesis of large area of graphene as recently reported makes it more interesting for modern use [23].…”

Nanocarbons with Different Dimensions as Noble-Metal-Free Co-Catalysts for Photocatalysts

“…Graphene, a new class of nanocarbon material with honeycomb network of monolayer carbon atoms, different from 0D fullerene and 1D CNTs or CNFs, has attracted increasing attention due to their excellent electrical conductivity, large surface area, and high chemical stability [63,64]. Graphene can be used as an electron-transport matrix due to its excellent electrical conductivity and perfect 2D feature, and then take the place of noble metals as co-catalysts for enhancing the photocatalytic performance by offering strong interaction, as shown in Figure 1.…”