Rational design of three-dimensional graphene/graphene oxide-based architectures for the efficient adsorption of contaminants from aqueous solutions

The removal of various contaminants from aqueous systems by adsorption has been proven to be one of the most recommended approaches for the treatment of wastewater. Many significant advantages, such as relatively low cost, good availability, ease of fabrication and high efficiency, are included in this technology. In addition, the adsorption of inorganic/organic substances from aqueous solutions is also a potential alternative for the recovery of valuable substances from wastewater. Three-dimensional (3D) graphene (Gr)- and graphene oxide (GO)-based architectures have shown many advantages, such as good selectivity and high effectiveness in the adsorption of metal ions or organic molecules, and even viruses at very low concentration levels. Adsorption by 3D Gr/GO-based architectures is a complex process, and possible mechanisms such as ion exchange, chelation, hydrogen bonding, electrostatic interactions, surface adsorption, p-π interactions, p-p interactions, π-π stacking and van der Waals interactions involved in the adsorption processes have been also discussed in detail. Herein, we present a critical review for the rational selection of effective and multifunctional components, as well as the fabrication of well-designed novel 3D Gr/GO composites for selective adsorption of specific contaminants, which can provide references for researchers in related fields.