Adsorption of dyes by nanomaterials: Recent developments and adsorption mechanisms

•Application of nanomaterials in dye wastewater treatment.•Specific adsorption mechanisms for different nano adsorbents.•Improvements in adsorption of dyes using nano material.•Categorization of dyes removed from water using nanomaterial.

Application of nanomaterials in dye wastewater treatment has received wide attention in recent years. This review highlights recent developments in the use of nanomaterials for the adsorption of dyes from wastewater. Specific adsorption mechanisms, improvements, particularly for increasing adsorption capacities, and toxicity are discussed for each nanomaterial. The accumulated data indicate that nanomaterials can be effectively used for treating dye wastewater. Nanochitosan, in particular, has a huge potential for commercial application due to its sustainability with respect to excellent adsorption performance, non-toxicity and low cost. Although the applications using nanomaterials have been developing rapidly, the technology is still far from achieving the ultimate goal of commercialization. Other considerations, such as regeneration methods and treatment of actual commercial textile dye wastewater, have not been sufficiently researched.