Graphene analogues in aquatic environments and porous media: dispersion, aggregation, deposition and transformation

The potential extensive application of graphene analogues (GAs), such as graphene, graphene oxide and reduced graphene oxide, in various fields results in the possibility of their release into the natural environment with negative impacts on humans and the ecosystem. The aggregation and transformation of GAs in aqueous solutions as well as the deposition of GAs on model environmental surfaces and in porous media control their fate, transport, and bio-toxicity in aquatic environments, aquatic-terrestrial transition zones and subsurface environments. The change in solution chemistry, physicochemical properties of GAs and interaction of GAs with water or a solid surface will alter the aggregation, deposition and transformation of GAs. The present review aims to provide a comprehensive overview of current knowledge concerning the aggregation, deposition and transformation of GAs with particular attention paid to the key factors governing the behavior of GAs in natural environments, which is a critical component of their life-cycle analysis, risk assessment, and waste management. We expect that this review can provide useful insights into some current knowledge gaps and can also reveal clues about needed future developments.