ABSTRACT
Azo dyes appear in almost all streams of wastewater and are
considered as primary pollutants for their mutagenic and
carcinogenic properties and biorecalcitrant nature. Recent studies
have proved adsorption to be a powerful technique for wastewater
treatment as it is inexpensive, easy to perform, and inert to toxic
substances. Graphene oxide (GO) is one such example of a new, cost-
effective, easy-to-use, and highly efficient adsorbent. The oxygenated
groups present on GO surfaces impart it a strong hydrophilic nature,
thereby facilitating its exfoliation in both water and other polar
organic solvents for the formation of stable suspensions. Previous
studies have reported the utilization of these oxygen-bearing groups
of GO as nucleation sites of metals or polymers for the synthesis of
different GO composites. In this chapter, the authors have compiled
recent studies addressing the synthesis of different GO composites
and their role in azo dye adsorption and established the same as an
environmentally benign approach for effluent treatment. Moreover,
a detailed discussion of adsorbent characterization, underlying
mechanisms, process optimization, environmental implications, and
future prospects has also been provided.